diff --git a/lua/markmap/init.lua b/lua/markmap/init.lua
index 6db47d4..cf9cac9 100644
--- a/lua/markmap/init.lua
+++ b/lua/markmap/init.lua
@@ -18,7 +18,7 @@ M.setup = function(ctx)
   -- Set default options
   if html_output == nil then
     if is_windows then -- windows
-      html_output = uv.os_getenv "TEMP" .. "markmap.html"
+      html_output = uv.os_getenv "TEMP" .. "\\" .. "markmap.html"
     elseif is_android then -- android
       html_output = "/data/data/com.termux/files/usr/tmp/markmap.html"
     else                   -- unix