I send mail by smtp protocol and javamail api. JavaMailSenderImpl sender = new JavaMailSenderImpl(); sender.setProtocol("smtp"); MimeMessage message = sender.createMimeMessage(); MimeMessageHelper helper = new MimeMessageHelper(message, true, "utf-8"); helper.setEncodeFilenames(true); helper.addAttachment(MimeUtility.encodeText("测试.docx", "UTF-8", "Q"), new ByteArrayResource(Base64Utils.decodeFromString("1111"))); sender.send(message);