diff --git a/src/pyj/read_book/view.pyj b/src/pyj/read_book/view.pyj
index 993265e027..20186d24ba 100644
--- a/src/pyj/read_book/view.pyj
+++ b/src/pyj/read_book/view.pyj
@@ -442,7 +442,7 @@ class View:
             self.iframe.style.backgroundColor = ans.background or 'white'
             bg_image = sd.get('background_image')
             if bg_image:
-                self.iframe.style.backgroundImage = f'url({READER_BACKGROUND_URL})' if runtime.is_standalone_viewer else f'url({bg_image})'
+                self.iframe.style.backgroundImage = f'url({READER_BACKGROUND_URL}?{Date().getTime()})' if runtime.is_standalone_viewer else f'url({bg_image})'
             else:
                 self.iframe.style.backgroundImage = 'none'
             if sd.get('background_image_style') is 'scaled':
diff --git a/src/pyj/viewer-main.pyj b/src/pyj/viewer-main.pyj
index f7fb8fc826..a14ee81769 100644
--- a/src/pyj/viewer-main.pyj
+++ b/src/pyj/viewer-main.pyj
@@ -241,8 +241,7 @@ def get_current_cfi(request_id):
 def background_image_changed(img_id):
     img = document.getElementById(img_id)
     if img:
-        img.src = ''
-        img.src = READER_BACKGROUND_URL
+        img.src = READER_BACKGROUND_URL + '?' + Date().getTime()
 
 
 def onerror(msg, script_url, line_number, column_number, error_object):