diff --git a/templates/snippets/file_view_js.html b/templates/snippets/file_view_js.html
index 5fb97052f8..c57589bd43 100644
--- a/templates/snippets/file_view_js.html
+++ b/templates/snippets/file_view_js.html
@@ -2,7 +2,11 @@
 <script type="text/javascript" src="{{MEDIA_URL}}codemirror/codemirror.js"></script>
 {% endif %}
 {% if filetype == 'PDF' %}
-<script type="text/javascript" src="{{MEDIA_URL}}js/pdf.js"></script>
+    {% if pdf_use_flash %}
+    <script type="text/javascript" src="{{MEDIA_URL}}flexpaper/js/flexpaper_flash.js"></script>
+    {% else %}
+    <script type="text/javascript" src="{{MEDIA_URL}}js/pdf.js"></script>
+    {% endif %}
 {% endif %}
 {% if filetype == 'Document' %}
 <script type="text/javascript" src="{{MEDIA_URL}}flexpaper/js/flexpaper_flash.js"></script>
diff --git a/templates/snippets/repo_file_get.html b/templates/snippets/repo_file_get.html
index d2fae69f4a..e4ec261b99 100644
--- a/templates/snippets/repo_file_get.html
+++ b/templates/snippets/repo_file_get.html
@@ -36,10 +36,8 @@
     }
 {% endif %}
 
-{% if filetype == 'PDF' %}
-if (!$.browser.mozilla && !$.browser.safari) {
-    $('#file-view').html('<p>在线查看：请使用firefox 或 chrome。</p>').addClass('file-view-tip');
-} else {
+{% if filetype == 'PDF' and not pdf_use_flash %}
+    // Use pdf.js to view pdf in firefox/chrome
     PDFJS.workerSrc = '{{MEDIA_URL}}js/pdf.js';
     $('#file-view').html('<div id="pdf"><img src="{{ MEDIA_URL }}pdf_full_view/images/loading-icon.gif" alt="加载中..." id="pdf-loading" style="margin-top:20px;" /><div id="pdf-op-bar" class="vh"><button id="prev">上一页</button><button id="next">下一页</button><span id="pdf-page"><label for="page-number">第</label> <input type="number" id="page-number" value="1" min="1"></input> / <span id="page-nums"></span> 页</span><button id="full-screen">全屏</button></div><canvas data="{{ raw_path }}" id="pdf-view" class="vh"></canvas></div>').css({'text-align':'center'});
     $('#pdf-op-bar').append($('#file-op').html());
@@ -89,7 +87,6 @@ if (!$.browser.mozilla && !$.browser.safari) {
             window.open('{{ SITE_ROOT }}pdf_full_view/?repo_id={{ repo.id }}&obj_id={{obj_id}}&file_name=' + e('{{ file_name }}'));
         });
     });
-}
 {% endif %}
 
 {% if filetype == 'Markdown' %}
@@ -108,7 +105,7 @@ if (!$.browser.mozilla && !$.browser.safari) {
     $('#file-view').html('<p>该类型文件无法在线查看。</p>').addClass('file-view-tip');
 {% endif %}
 
-{% if filetype == 'Document' %}
+{% if filetype == 'Document' or filetype == 'PDF' and pdf_use_flash %}
   {% if err %}
   $('#file-view').html('<p class="error">{{ err }}</p>').addClass('file-view-tip');
   {% else %}
@@ -144,7 +141,7 @@ if (!$.browser.mozilla && !$.browser.safari) {
           $('#file-view').children('object').prepend('<param name="wmode" value="opaque">'); //allow popup to show on top of the flash
   }
   
-  {% if document_swf_exists %}
+  {% if swf_exists %}
   load_flexpaper();
   {% else %}
   function check_status () {
@@ -176,7 +173,7 @@ if (!$.browser.mozilla && !$.browser.safari) {
           },
           error: function(xhr, ajaxOptions, thrownError) {
               var jsonVal = jQuery.parseJSON(xhr.responseText);
-              $('#file-view').html('<p class="error">' + jsonVal[0]['error'] + '</p>');
+              $('#file-view').html('<p class="error">' + jsonVal['error'] + '</p>');
           }
       });
   }
diff --git a/views.py b/views.py
index 61d3c67529..d916e9ba85 100644
--- a/views.py
+++ b/views.py
@@ -1025,11 +1025,16 @@ def repo_view_file(request, repo_id):
     # get file content
     err = ''
     file_content = ''
-    document_swf_exists = False
+    swf_exists = False
+    pdf_use_flash = False
     if filetype == 'Text' or filetype == 'Markdown':
         err, file_content, encoding, newline_mode = repo_file_get(raw_path)
     elif filetype == 'Document':
-        err, document_swf_exists = document_prepare(raw_path, obj_id, fileext)
+        err, swf_exists = flash_prepare(raw_path, obj_id, fileext)
+    elif filetype == 'PDF':
+        pdf_use_flash = use_flash_for_pdf(request)
+        if pdf_use_flash:
+            err, swf_exists = flash_prepare(raw_path, obj_id, 'pdf')
     
     # file share link
     l = FileShare.objects.filter(repo_id=repo_id).filter(\
@@ -1093,7 +1098,8 @@ def repo_view_file(request, repo_id):
             'groups': groups,
             'comments': comments,
             'comment_open':comment_open,
-            'document_swf_exists': document_swf_exists,
+            'swf_exists': swf_exists,
+            'pdf_use_flash': pdf_use_flash,
             'DOCUMENT_CONVERTOR_ROOT': DOCUMENT_CONVERTOR_ROOT,
             'contributors': contributors,
             'latest_contributor': latest_contributor,
@@ -2192,8 +2198,16 @@ def view_shared_file(request, token):
     # get file content
     err = ''
     file_content = ''
+    swf_exists = False
+    pdf_use_flash = False
     if filetype == 'Text' or filetype == 'Markdown':
         err, file_content, encoding, newline_mode = repo_file_get(raw_path)
+    elif filetype == 'Document':
+        err, swf_exists = flash_prepare(raw_path, obj_id, fileext)
+    elif filetype == 'PDF':
+        pdf_use_flash = use_flash_for_pdf(request)
+        if pdf_use_flash:
+            err, swf_exists = flash_prepare(raw_path, obj_id, 'pdf')
     
     # Increase file shared link view_cnt, this operation should be atomic
     fileshare = FileShare.objects.get(token=token)
@@ -2213,6 +2227,9 @@ def view_shared_file(request, token):
             'username': username,
             'err': err,
             'file_content': file_content,
+            'swf_exists': swf_exists,
+            'pdf_use_flash': pdf_use_flash,
+            'DOCUMENT_CONVERTOR_ROOT': DOCUMENT_CONVERTOR_ROOT,
             }, context_instance=RequestContext(request))
 
 @login_required
@@ -2284,7 +2301,7 @@ def send_shared_link(request):
         return HttpResponseBadRequest(json.dumps(form.errors),
                                       content_type=content_type)
 
-def document_prepare(raw_path, obj_id, doctype):
+def flash_prepare(raw_path, obj_id, doctype):
     curl = DOCUMENT_CONVERTOR_ROOT + 'convert'
     data = {'doctype': doctype,
             'file_id': obj_id,
@@ -2300,3 +2317,16 @@ def document_prepare(raw_path, obj_id, doctype):
             return ret_dict['error'], False
         else:
             return None, ret_dict['exists']
+
+def use_flash_for_pdf(request):
+    """Decide whether to use flash to view pdf file, according to the current
+    browser type and version.
+
+    """
+    ua = request.META.get('HTTP_USER_AGENT', '')
+    if 'MSIE' in ua:
+        return True
+    else:
+        return False
+    
+