diff --git a/api/v1/document.pb.go b/api/v1/document.pb.go
index 559afb2..d151a2f 100644
--- a/api/v1/document.pb.go
+++ b/api/v1/document.pb.go
@@ -68,6 +68,7 @@ type Document struct {
 	User            *User       `protobuf:"bytes,31,opt,name=user,proto3" json:"user,omitempty"`
 	EnableGzip      bool        `protobuf:"varint,32,opt,name=enable_gzip,json=enableGzip,proto3" json:"enable_gzip,omitempty"`
 	ConvertError    string      `protobuf:"bytes,33,opt,name=convert_error,json=convertError,proto3" json:"convert_error,omitempty"`
+	PreviewExt      string      `protobuf:"bytes,34,opt,name=preview_ext,json=previewExt,proto3" json:"preview_ext,omitempty"`
 }
 
 func (m *Document) Reset()         { *m = Document{} }
@@ -334,6 +335,13 @@ func (m *Document) GetConvertError() string {
 	return ""
 }
 
+func (m *Document) GetPreviewExt() string {
+	if m != nil {
+		return m.PreviewExt
+	}
+	return ""
+}
+
 // 删除文档，放入回收站
 type DeleteDocumentRequest struct {
 	Id []int64 `protobuf:"varint,1,rep,packed,name=id,proto3" json:"id,omitempty"`
@@ -1381,116 +1389,117 @@ func init() {
 func init() { proto.RegisterFile("api/v1/document.proto", fileDescriptor_55a584ae3a7fc022) }
 
 var fileDescriptor_55a584ae3a7fc022 = []byte{
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+	0x03, 0x90, 0xff, 0x27, 0x3f, 0xd7, 0xbe, 0x7a, 0x34, 0x0d, 0x22, 0xea, 0x06, 0x23, 0x09, 0xf4,
+	0xc9, 0xcd, 0xb3, 0x37, 0x9b, 0x48, 0xf6, 0xa3, 0xff, 0x05, 0x00, 0x00, 0xff, 0xff, 0x7a, 0xf8,
+	0xb0, 0xc9, 0xdc, 0x14, 0x00, 0x00,
 }
 
 // Reference imports to suppress errors if they are not otherwise used.
@@ -2277,6 +2286,15 @@ func (m *Document) MarshalToSizedBuffer(dAtA []byte) (int, error) {
 	_ = i
 	var l int
 	_ = l
+	if len(m.PreviewExt) > 0 {
+		i -= len(m.PreviewExt)
+		copy(dAtA[i:], m.PreviewExt)
+		i = encodeVarintDocument(dAtA, i, uint64(len(m.PreviewExt)))
+		i--
+		dAtA[i] = 0x2
+		i--
+		dAtA[i] = 0x92
+	}
 	if len(m.ConvertError) > 0 {
 		i -= len(m.ConvertError)
 		copy(dAtA[i:], m.ConvertError)
@@ -3578,6 +3596,10 @@ func (m *Document) Size() (n int) {
 	if l > 0 {
 		n += 2 + l + sovDocument(uint64(l))
 	}
+	l = len(m.PreviewExt)
+	if l > 0 {
+		n += 2 + l + sovDocument(uint64(l))
+	}
 	return n
 }
 
@@ -4907,6 +4929,38 @@ func (m *Document) Unmarshal(dAtA []byte) error {
 			}
 			m.ConvertError = string(dAtA[iNdEx:postIndex])
 			iNdEx = postIndex
+		case 34:
+			if wireType != 2 {
+				return fmt.Errorf("proto: wrong wireType = %d for field PreviewExt", wireType)
+			}
+			var stringLen uint64
+			for shift := uint(0); ; shift += 7 {
+				if shift >= 64 {
+					return ErrIntOverflowDocument
+				}
+				if iNdEx >= l {
+					return io.ErrUnexpectedEOF
+				}
+				b := dAtA[iNdEx]
+				iNdEx++
+				stringLen |= uint64(b&0x7F) << shift
+				if b < 0x80 {
+					break
+				}
+			}
+			intStringLen := int(stringLen)
+			if intStringLen < 0 {
+				return ErrInvalidLengthDocument
+			}
+			postIndex := iNdEx + intStringLen
+			if postIndex < 0 {
+				return ErrInvalidLengthDocument
+			}
+			if postIndex > l {
+				return io.ErrUnexpectedEOF
+			}
+			m.PreviewExt = string(dAtA[iNdEx:postIndex])
+			iNdEx = postIndex
 		default:
 			iNdEx = preIndex
 			skippy, err := skipDocument(dAtA[iNdEx:])
diff --git a/api/v1/document.proto b/api/v1/document.proto
index d08ee1a..92fc8cd 100644
--- a/api/v1/document.proto
+++ b/api/v1/document.proto
@@ -53,6 +53,7 @@ message Document {
   User user = 31;                     // 文档作者
   bool enable_gzip = 32;              // 是否启用gzip压缩
   string convert_error = 33;          // 转换错误信息
+  string preview_ext = 34;            // 预览文件扩展名
 }
 
 // 删除文档，放入回收站
diff --git a/biz/attachment.go b/biz/attachment.go
index e76474c..605bc35 100644
--- a/biz/attachment.go
+++ b/biz/attachment.go
@@ -247,11 +247,16 @@ func (s *AttachmentAPIService) ViewDocumentPages(ctx *gin.Context) {
 		return
 	}
 	page := strings.TrimLeft(ctx.Param("page"), "./")
-	if strings.HasSuffix(page, ".gzip.svg") {
-		ctx.Header("Content-Encoding", "gzip")
+	if strings.HasSuffix(page, ".svg") {
+		if strings.HasSuffix(page, ".gzip.svg") {
+			ctx.Header("Content-Encoding", "gzip")
+		}
+		ctx.Header("Content-Type", "image/svg+xml")
 	}
-	ctx.Header("Content-Type", "image/svg+xml")
-	ctx.File(fmt.Sprintf("documents/%s/%s/%s", strings.Join(strings.Split(hash, "")[:5], "/"), hash, page))
+
+	file := fmt.Sprintf("documents/%s/%s/%s", strings.Join(strings.Split(hash, "")[:5], "/"), hash, page)
+	s.logger.Debug("ViewDocumentPages", zap.String("hash", hash), zap.String("page", page), zap.String("file", file))
+	ctx.File(file)
 }
 
 func (s *AttachmentAPIService) ViewDocumentCover(ctx *gin.Context) {
diff --git a/model/config.go b/model/config.go
index 5a4ee79..1b0fb05 100644
--- a/model/config.go
+++ b/model/config.go
@@ -267,6 +267,7 @@ const (
 	ConfigConverterEnableSVGO                    = "enable_svgo"                      // 是否启用 SVGO
 	ConfigConverterEnableGZIP                    = "enable_gzip"                      // 是否启用 GZIP
 	ConfigConverterEnableConvertRepeatedDocument = "enable_convert_repeated_document" // 是否转换已转换的重复文档
+	ConfigConverterExtension                     = "extension"                        // 转换后的文件扩展名，即以什么方式来浏览文档，支持 jpg、png、svg，默认为svg，pdf和html暂不支持
 )
 
 const (
@@ -301,6 +302,7 @@ type ConfigConverter struct {
 	EnableGZIP                    bool `json:"enable_gzip"`                      // 是否对svg启用GZIP压缩。转换效率会有所下降。相对直接的svg文件，可以节省3/4的存储空间
 	EnableConvertRepeatedDocument bool `json:"enable_convert_repeated_document"` // 是否转换已转换的重复文档。如果开启，会导致转换效率下降，但是可以节省大量的存储空间
 	// GZIP和svgo都开启，转换效率会有所下降，可以综合节省约85%的存储空间
+	Extension string `json:"extension"` // 转换后的文件扩展名，即以什么方式来浏览文档，支持 jpg、png、svg，默认为svg，pdf和html暂不支持
 }
 
 const (
@@ -696,11 +698,12 @@ func (m *DBModel) initConfig() (err error) {
 		{Category: ConfigCategoryFooter, Name: ConfigFooterFeedback, Label: "意见反馈", Value: "/article/feedback", Placeholder: "请输入意见反馈的链接地址，留空表示不显示", InputType: InputTypeText, Sort: 28, Options: ""},
 
 		// 转换配置项
-		{Category: ConfigCategoryConverter, Name: ConfigConverterMaxPreview, Label: "最大预览页数", Value: "12", Placeholder: "文档允许的最大预览页数，0表示不限制", InputType: InputTypeNumber, Sort: 15, Options: ""},
-		{Category: ConfigCategoryConverter, Name: ConfigConverterTimeout, Label: "转换超时(分钟)", Value: "30", Placeholder: "文档转换超时时间，默认为30分钟", InputType: InputTypeNumber, Sort: 16, Options: ""},
-		{Category: ConfigCategoryConverter, Name: ConfigConverterEnableGZIP, Label: "是否启用GZIP压缩", Value: "true", Placeholder: "是否对文档SVG预览文件启用GZIP压缩，启用后转换效率会【稍微】下降，但相对直接的SVG文件减少75%的存储空间", InputType: InputTypeSwitch, Sort: 17, Options: ""},
-		{Category: ConfigCategoryConverter, Name: ConfigConverterEnableSVGO, Label: "是否启用SVGO", Value: "false", Placeholder: "是否对文档SVG预览文件启用SVGO压缩，启用后转换效率会【明显】下降，但相对直接的SVG文件减少50%左右的存储空间", InputType: InputTypeSwitch, Sort: 18, Options: ""},
-		{Category: ConfigCategoryConverter, Name: ConfigConverterEnableConvertRepeatedDocument, Label: "是否转换重复文档", Value: "false", Placeholder: "对于已转换过的文档，再次被上传时是否再转换一次", InputType: InputTypeSwitch, Sort: 20, Options: ""},
+		{Category: ConfigCategoryConverter, Name: ConfigConverterMaxPreview, Label: "最大预览页数", Value: "12", Placeholder: "文档允许的最大预览页数，0表示不限制", InputType: InputTypeNumber, Sort: 0, Options: ""},
+		{Category: ConfigCategoryConverter, Name: ConfigConverterTimeout, Label: "转换超时(分钟)", Value: "30", Placeholder: "文档转换超时时间，默认为30分钟", InputType: InputTypeNumber, Sort: 10, Options: ""},
+		{Category: ConfigCategoryConverter, Name: ConfigConverterExtension, Label: "预览格式", Value: "svg", Placeholder: "将文档转为特定格式以供预览", InputType: InputTypeSelect, Sort: 20, Options: "svg:SVG\njpg:JPEG\npng:PNG"},
+		{Category: ConfigCategoryConverter, Name: ConfigConverterEnableGZIP, Label: "是否启用GZIP压缩", Value: "true", Placeholder: "是否对文档SVG预览文件启用GZIP压缩，启用后转换效率会【稍微】下降，但相对直接的SVG文件减少75%的存储空间", InputType: InputTypeSwitch, Sort: 30, Options: ""},
+		{Category: ConfigCategoryConverter, Name: ConfigConverterEnableSVGO, Label: "是否启用SVGO", Value: "false", Placeholder: "是否对文档SVG预览文件启用SVGO压缩，启用后转换效率会【明显】下降，但相对直接的SVG文件减少50%左右的存储空间", InputType: InputTypeSwitch, Sort: 40, Options: ""},
+		{Category: ConfigCategoryConverter, Name: ConfigConverterEnableConvertRepeatedDocument, Label: "是否转换重复文档", Value: "false", Placeholder: "对于已转换过的文档，再次被上传时是否再转换一次", InputType: InputTypeSwitch, Sort: 50, Options: ""},
 
 		// 下载配置
 		{Category: ConfigCategoryDownload, Name: ConfigDownloadEnableGuestDownload, Label: "是否允许游客下载", Value: "false", Placeholder: "启用之后，未登录用户可以下载免费文档", InputType: InputTypeSwitch, Sort: 10, Options: ""},
diff --git a/model/document.go b/model/document.go
index 6e77bc3..b80858f 100644
--- a/model/document.go
+++ b/model/document.go
@@ -63,6 +63,7 @@ type Document struct {
 	DeletedUserId int64           `form:"deleted_user_id" json:"deleted_user_id,omitempty" gorm:"column:deleted_user_id;type:bigint(20);size:20;default:0;comment:删除用户ID;"`
 	EnableGZIP    bool            `form:"enable_gzip" json:"enable_gzip,omitempty" gorm:"column:enable_gzip;type:tinyint(1);size:1;default:0;comment:是否启用GZIP压缩;"`
 	RecommendAt   *time.Time      `form:"recommend_at" json:"recommend_at,omitempty" gorm:"column:recommend_at;type:datetime;comment:推荐时间;index:idx_recommend_at;"`
+	PreviewExt    string          `form:"preview_ext" json:"preview_ext,omitempty" gorm:"column:preview_ext;type:varchar(16);size:16;default:.svg;comment:预览图扩展名;"`
 }
 
 func (Document) TableName() string {
@@ -701,18 +702,23 @@ func (m *DBModel) ConvertDocument() (err error) {
 		toPage = document.Pages
 	}
 
-	pages, err = cvt.ConvertPDFToSVG(dstPDF, 1, toPage, cfg.EnableSVGO, cfg.EnableGZIP)
+	pages, err = cvt.ConvertPDFToPages(dstPDF, 1, toPage, &converter.OptionConvertPages{
+		EnableSVGO: cfg.EnableSVGO,
+		EnableGZIP: cfg.EnableGZIP,
+		Extension:  cfg.Extension,
+	})
 	if err != nil {
 		m.SetDocumentStatus(document.Id, DocumentStatusFailed)
 		m.logger.Error("ConvertDocument", zap.Error(err))
 		return
 	}
 
+	ext := "." + cfg.Extension
+	if ext == ".svg" && cfg.EnableGZIP {
+		ext = ".gzip.svg"
+	}
+
 	for _, page := range pages {
-		ext := ".svg"
-		if strings.HasSuffix(page.PagePath, ".gzip.svg") {
-			ext = ".gzip.svg"
-		}
 		dst := fmt.Sprintf(baseDir+"/%d%s", page.PageNum, ext)
 		m.logger.Debug("ConvertDocument CopyFile", zap.String("src", page.PagePath), zap.String("dst", dst))
 		errCopy := util.CopyFile(page.PagePath, dst)
@@ -734,7 +740,8 @@ func (m *DBModel) ConvertDocument() (err error) {
 
 	document.Status = DocumentStatusConverted
 	document.EnableGZIP = cfg.EnableGZIP
-	err = m.db.Select("description", "cover", "width", "height", "preview", "pages", "status", "enable_gzip").Where("id = ?", document.Id).Updates(document).Error
+	document.PreviewExt = ext
+	err = m.db.Select("description", "cover", "width", "height", "preview", "pages", "status", "enable_gzip", "preview_ext").Where("id = ?", document.Id).Updates(document).Error
 	if err != nil {
 		m.SetDocumentStatus(document.Id, DocumentStatusFailed)
 		m.logger.Error("ConvertDocument", zap.Error(err))
diff --git a/util/converter/converter.go b/util/converter/converter.go
index ac6d8bc..a78d9ff 100644
--- a/util/converter/converter.go
+++ b/util/converter/converter.go
@@ -26,6 +26,7 @@ const (
 	mutool       = "mutool"
 	inkscape     = "inkscape"
 	dirDteFmt    = "2006/01/02"
+	imageMagick  = "convert"
 )
 
 type ConvertCallback func(page int, pagePath string, err error)
@@ -167,6 +168,54 @@ func (c *Converter) ConvertPDFToSVG(src string, fromPage, toPage int, enableSVGO
 	return
 }
 
+type OptionConvertPages struct {
+	EnableSVGO bool
+	EnableGZIP bool
+	Extension  string
+}
+
+// ConvertPDFToPages 将PDF转为预览页
+func (c *Converter) ConvertPDFToPages(src string, fromPage, toPage int, option *OptionConvertPages) (pages []Page, err error) {
+	switch strings.TrimLeft(option.Extension, ".") {
+	case "png":
+		return c.ConvertPDFToPNG(src, fromPage, toPage)
+	case "jpg":
+		// 见将pdf转为png，然后png再转为jpg
+		pages, err = c.ConvertPDFToPNG(src, fromPage, toPage)
+		// 通过imagemagick将图片转为jpg
+		for idx, page := range pages {
+			if dst, errConvert := c.ConvertPNGToJPG(page.PagePath); errConvert == nil {
+				os.Remove(page.PagePath)
+				page.PagePath = dst
+				pages[idx] = page
+			}
+		}
+		return pages, err
+	default: // 默认转为svg
+		return c.ConvertPDFToSVG(src, fromPage, toPage, option.EnableSVGO, option.EnableGZIP)
+	}
+}
+
+// 将png转为jpg
+func (c *Converter) ConvertPNGToJPG(src string) (dst string, err error) {
+	dst = strings.TrimSuffix(src, filepath.Ext(src)) + ".jpg"
+	// 通过imagemagick将图片转为jpg
+	args := []string{
+		src,
+		dst,
+	}
+	c.logger.Debug("convert png to jpg", zap.String("cmd", imageMagick), zap.Strings("args", args))
+	_, err = command.ExecCommand(imageMagick, args, c.timeout)
+	if err != nil {
+		c.logger.Error("convert png to jpg", zap.String("cmd", imageMagick), zap.Strings("args", args), zap.Error(err))
+	}
+	return
+}
+
+func (c *Converter) ConvertPDFToJPG(src string, fromPage, toPage int) (pages []Page, err error) {
+	return c.convertPDFToPage(src, fromPage, toPage, ".jpg")
+}
+
 // ConvertPDFToPNG 将PDF转为PNG
 func (c *Converter) ConvertPDFToPNG(src string, fromPage, toPage int) (pages []Page, err error) {
 	return c.convertPDFToPage(src, fromPage, toPage, ".png")
diff --git a/web/pages/document/_id.vue b/web/pages/document/_id.vue
index 1d3af1f..e27d0ef 100644
--- a/web/pages/document/_id.vue
+++ b/web/pages/document/_id.vue
@@ -416,7 +416,7 @@ import {
   getDocumentScore,
 } from '~/api/document'
 import { getFavorite, createFavorite, deleteFavorite } from '~/api/favorite'
-import { formatDatetime, formatBytes, getIcon } from '~/utils/utils'
+import { formatDatetime, formatBytes, getIcon, genPrevPage } from '~/utils/utils'
 import { documentStatusOptions } from '~/utils/enum'
 import QRCode from 'qrcodejs2' // 引入qrcode
 import FormComment from '~/components/FormComment.vue'
@@ -555,9 +555,7 @@ export default {
       // 限定预览页数，拼装图片链接
       const pages = []
       for (let i = 1; i <= preview; i++) {
-        const src = doc.enable_gzip
-          ? `/view/page/${doc.attachment.hash}/${i}.gzip.svg`
-          : `/view/page/${doc.attachment.hash}/${i}.svg`
+        const src= genPrevPage(doc.attachment.hash, i, doc.preview_ext, doc.enable_gzip)
         pages.push({
           lazySrc: src,
           src: src,
@@ -879,9 +877,7 @@ export default {
       if (document.fullscreenElement) startLazyLoad = 5
       for (let i = this.pages.length + 1; i <= end; i++) {
         j += 1
-        const src = this.document.enable_gzip
-          ? `/view/page/${this.document.attachment.hash}/${i}.gzip.svg`
-          : `/view/page/${this.document.attachment.hash}/${i}.svg`
+        const src= genPrevPage(this.document.attachment.hash, i, this.document.preview_ext, this.document.enable_gzip)
         this.pages.push({
           // 前两页，直接不要懒加载，如果非全屏
           src: j <= startLazyLoad ? src : this.loadingImage,
diff --git a/web/utils/utils.js b/web/utils/utils.js
index 8a4cccb..24c1d61 100644
--- a/web/utils/utils.js
+++ b/web/utils/utils.js
@@ -279,3 +279,13 @@ export function genTimeDuration(duration) {
   }
   return [start.Format(fmt), new Date().Format(fmt)]
 }
+
+export function genPrevPage(hash, pageNO, ext, enableGZIP){
+  if (!ext){
+    ext=".svg"
+  }
+  if (ext===".svg" && enableGZIP){
+    ext=".gzip.svg"
+  }
+  return  `/view/page/${hash}/${pageNO}${ext}`
+}
\ No newline at end of file