try {
           // fileName = new String(fileName.getBytes("UTF-8"), "UTF-8");
           //if (request.getHeader("User-Agent").toLowerCase().indexOf("firefox") > 0)

             fileName = new String(fileName.getBytes("UTF-8"), "ISO8859-1");//firefox浏览器
                
//                else 
//
//                    if (request.getHeader("User-Agent").toUpperCase().indexOf("MSIE") > 0)
//
//                    fileName = URLEncoder.encode(fileName, "UTF-8");//IE浏览器 
        } catch (UnsupportedEncodingException e) {
            // should no happen
        }
        System.out.println(fileName);
        response.reset();
        response.setContentType("application/msexcel;charset=UTF-8");
        response.setHeader("Content-disposition", "attachment;filename= " + fileName);
    }

------解决方案--------------------
                        String downloadName = "表名.xls";
			downloadName = new String(downloadName.getBytes(), "ISO8859-1");
			response.setHeader("Content-disposition",   "attachment;filename=" + downloadName);
			response.setContentType("application/x-download");
			
			ServletOutputStream servletOutputStream = response.getOutputStream();
			wb.write(servletOutputStream);
			servletOutputStream.flush();
			servletOutputStream.close();