python 3的另一种方法(如果有人正在搜索):

import smtplib
from email.mime.multipart import MIMEMultipart
from email.mime.text import MIMEText
from email.mime.base import MIMEBase
from email import encoders

fromaddr = "sender mail address"
toaddr = "receiver mail address"

msg = MIMEMultipart()

msg['From'] = fromaddr
msg['To'] = toaddr
msg['Subject'] = "SUBJECT OF THE EMAIL"

body = "TEXT YOU WANT TO SEND"

msg.attach(MIMEText(body, 'plain'))

filename = "fileName"
attachment = open("path of file", "rb")

part = MIMEBase('application', 'octet-stream')
part.set_payload((attachment).read())
encoders.encode_base64(part)
part.add_header('Content-Disposition', "attachment; filename= %s" % filename)

msg.attach(part)

server = smtplib.SMTP('smtp.gmail.com', 587)
server.starttls()
server.login(fromaddr, "sender mail password")
text = msg.as_string()
server.sendmail(fromaddr, toaddr, text)
server.quit()

确保在你的Gmail帐户上允许“不太安全的应用程序”

因为这里有很多关于Python 3的答案，但没有一个说明如何使用Python 3.6中经过彻底检查的电子邮件库，这里是从当前电子邮件示例文档中快速复制+粘贴。 (我略去了一些内容，以去除猜测正确MIME类型之类的多余内容。)

以Python >3.5为目标的现代代码不应该再使用email.message.Message API(包括各种MIMEText、MIMEMultipart、MIMEBase等类)或更老的mimetypes。

from email.message import EmailMessage
import smtplib

msg = EmailMessage()
msg["Subject"] = "Our family reunion"
msg["From"] = "me <sender@example.org>"
msg["To"] = "recipient <victim@example.net>"
# definitely don't mess with the .preamble

msg.set_content("Hello, victim! Look at these pictures")

with open("path/to/attachment.png", "rb") as fp:
    msg.add_attachment(
        fp.read(), maintype="image", subtype="png")

# Notice how smtplib now includes a send_message() method
with smtplib.SMTP("localhost") as s:
    s.send_message(msg)

The modern email.message.EmailMessage API is now quite a bit more versatile and logical than the older version of the library. There are still a few kinks around the presentation in the documentation (it's not obvious how to change the Content-Disposition: of an attachment, for example; and the discussion of the policy module is probably too obscure for most newcomers) and fundamentally, you still need to have some sort of idea of what the MIME structure should look like (though the library now finally takes care of a lot of the nitty-gritty around that). Perhaps see What are the "parts" in a multipart email? for a brief introduction.

Using localhost as your SMTP server obviously only works if you actually have an SMTP server running on your local computer. Properly getting email off your system is a fairly complex separate question. For simple requirements, probably use your existing email account and your provider's email server (search for examples of using port 587 with Google, Yahoo, or whatever you have - what exactly works depends somewhat on the provider; some will only support port 465, or legacy port 25 which is however now by and large impossible to use on public-facing servers because of spam filtering).

这是我最终使用的代码:

import smtplib
from email.MIMEMultipart import MIMEMultipart
from email.MIMEBase import MIMEBase
from email import Encoders


SUBJECT = "Email Data"

msg = MIMEMultipart()
msg['Subject'] = SUBJECT 
msg['From'] = self.EMAIL_FROM
msg['To'] = ', '.join(self.EMAIL_TO)

part = MIMEBase('application', "octet-stream")
part.set_payload(open("text.txt", "rb").read())
Encoders.encode_base64(part)
    
part.add_header('Content-Disposition', 'attachment; filename="text.txt"')

msg.attach(part)

server = smtplib.SMTP(self.EMAIL_SERVER)
server.sendmail(self.EMAIL_FROM, self.EMAIL_TO, msg.as_string())

代码与Oli的帖子大致相同。

代码基于二进制文件电子邮件附件问题的帖子。

这是另一个:

import smtplib
from os.path import basename
from email.mime.application import MIMEApplication
from email.mime.multipart import MIMEMultipart
from email.mime.text import MIMEText
from email.utils import COMMASPACE, formatdate


def send_mail(send_from, send_to, subject, text, files=None,
              server="127.0.0.1"):
    assert isinstance(send_to, list)

    msg = MIMEMultipart()
    msg['From'] = send_from
    msg['To'] = COMMASPACE.join(send_to)
    msg['Date'] = formatdate(localtime=True)
    msg['Subject'] = subject

    msg.attach(MIMEText(text))

    for f in files or []:
        with open(f, "rb") as fil:
            part = MIMEApplication(
                fil.read(),
                Name=basename(f)
            )
        # After the file is closed
        part['Content-Disposition'] = 'attachment; filename="%s"' % basename(f)
        msg.attach(part)


    smtp = smtplib.SMTP(server)
    smtp.sendmail(send_from, send_to, msg.as_string())
    smtp.close()

这和第一个例子差不多……但顺便来一下应该更容易些。

下面是我从SoccerPlayer的帖子中找到的内容的组合，下面的链接使我更容易附加一个xlsx文件。在这里找到

file = 'File.xlsx'
username=''
password=''
send_from = ''
send_to = 'recipient1 , recipient2'
Cc = 'recipient'
msg = MIMEMultipart()
msg['From'] = send_from
msg['To'] = send_to
msg['Cc'] = Cc
msg['Date'] = formatdate(localtime = True)
msg['Subject'] = ''
server = smtplib.SMTP('smtp.gmail.com')
port = '587'
fp = open(file, 'rb')
part = MIMEBase('application','vnd.ms-excel')
part.set_payload(fp.read())
fp.close()
encoders.encode_base64(part)
part.add_header('Content-Disposition', 'attachment', filename='Name File Here')
msg.attach(part)
smtp = smtplib.SMTP('smtp.gmail.com')
smtp.ehlo()
smtp.starttls()
smtp.login(username,password)
smtp.sendmail(send_from, send_to.split(',') + msg['Cc'].split(','), msg.as_string())
smtp.quit()

其他的答案也很好，但我还是想分享一种不同的方法，以防有人正在寻找替代方案。

主要的区别是，使用这种方法，你可以使用HTML/CSS来格式化你的邮件，所以你可以有创意，给你的电子邮件一些样式。虽然没有强制使用HTML，但仍然可以只使用纯文本。

注意，该函数接受将电子邮件发送给多个收件人，也允许附加多个文件。

我只在python2上尝试过，但我认为它在python3上也能正常工作:

import os.path
import smtplib
from email.mime.multipart import MIMEMultipart
from email.mime.text import MIMEText
from email.mime.application import MIMEApplication

def send_email(subject, message, from_email, to_email=[], attachment=[]):
    """
    :param subject: email subject
    :param message: Body content of the email (string), can be HTML/CSS or plain text
    :param from_email: Email address from where the email is sent
    :param to_email: List of email recipients, example: ["a@a.com", "b@b.com"]
    :param attachment: List of attachments, exmaple: ["file1.txt", "file2.txt"]
    """
    msg = MIMEMultipart()
    msg['Subject'] = subject
    msg['From'] = from_email
    msg['To'] = ", ".join(to_email)
    msg.attach(MIMEText(message, 'html'))

    for f in attachment:
        with open(f, 'rb') as a_file:
            basename = os.path.basename(f)
            part = MIMEApplication(a_file.read(), Name=basename)

        part['Content-Disposition'] = 'attachment; filename="%s"' % basename
        msg.attach(part)

    email = smtplib.SMTP('your-smtp-host-name.com')
    email.sendmail(from_email, to_email, msg.as_string())

我希望这能有所帮助!: -)