1、首先备份Ubuntu 12.04源列表

sudo cp /etc/apt/sources.list /etc/apt/sources.list.backup （备份下当前的源列表，有备无患嘛）

2、修改更新源

sudo gedit /etc/apt/sources.list （打开Ubuntu 12.04源列表文件）

3、将下面的代码粘贴进去（“#”开头的那一行为注释，可以直接复制进文件中）

4、通知ubuntu启用新的更新源 sudo apt-get update

#台湾源

deb http://tw.archive.ubuntu.com/ubuntu/ precise main universe restricted multiverse

deb-src http://tw.archive.ubuntu.com/ubuntu/ precise main universe restricted multiverse

deb http://tw.archive.ubuntu.com/ubuntu/ precise-security universe main multiverse restricted

deb-src http://tw.archive.ubuntu.com/ubuntu/ precise-security universe main multiverse restricted

deb http://tw.archive.ubuntu.com/ubuntu/ precise-updates universe main multiverse restricted

deb-src http://tw.archive.ubuntu.com/ubuntu/ precise-updates universe main multiverse restricted

#网易 Ubuntu 11.10 源（速度很快）

deb http://mirrors.163.com/ubuntu/ precise main universe restricted multiverse

deb-src http://mirrors.163.com/ubuntu/ precise main universe restricted multiverse

deb http://mirrors.163.com/ubuntu/ precise-security universe main multiverse restricted

deb-src http://mirrors.163.com/ubuntu/ precise-security universe main multiverse restricted

deb http://mirrors.163.com/ubuntu/ precise-updates universe main multiverse restricted

deb http://mirrors.163.com/ubuntu/ precise-proposed universe main multiverse restricted

deb-src http://mirrors.163.com/ubuntu/ precise-proposed universe main multiverse restricted

deb http://mirrors.163.com/ubuntu/ precise-backports universe main multiverse restricted

deb-src http://mirrors.163.com/ubuntu/ precise-backports universe main multiverse restricted

deb-src http://mirrors.163.com/ubuntu/ precise-updates universe main multiverse restricted

#骨头源，骨头源是bones7456架设的一个Ubuntu源 ，提供ubuntu,deepin

deb http://ubuntu.srt.cn/ubuntu/ precise main universe restricted multiverse

deb-src http://ubuntu.srt.cn/ubuntu/ precise main universe restricted multiverse

deb http://ubuntu.srt.cn/ubuntu/ precise-security universe main multiverse restricted

deb-src http://ubuntu.srt.cn/ubuntu/ precise-security universe main multiverse restricted

deb http://ubuntu.srt.cn/ubuntu/ precise-updates universe main multiverse restricted

deb http://ubuntu.srt.cn/ubuntu/ precise-proposed universe main multiverse restricted

deb-src http://ubuntu.srt.cn/ubuntu/ precise-proposed universe main multiverse restricted

deb http://ubuntu.srt.cn/ubuntu/ precise-backports universe main multiverse restricted

deb-src http://ubuntu.srt.cn/ubuntu/ precise-backports universe main multiverse restricted

deb-src http://ubuntu.srt.cn/ubuntu/ precise-updates universe main multiverse restricted

#mirror.lupaworld.com的源，速度很快

deb http://mirror.lupaworld.com/ubuntu/archive/ precise main restricted universe multiverse

deb http://mirror.lupaworld.com/ubuntu/archive/ precise-security main restricted universe multiverse

deb http://mirror.lupaworld.com/ubuntu/archive/ precise-updates main restricted universe multiverse

deb http://mirror.lupaworld.com/ubuntu/archive/ precise-backports main restricted universe multiverse

deb http://mirror.lupaworld.com/ubuntu/ubuntu-cn/ precise main restricted universe multiverse

#ubuntu.cn99.com源（推荐）:

deb http://ubuntu.cn99.com/ubuntu/ precise main restricted universe multiverse

deb http://ubuntu.cn99.com/ubuntu/ precise-updates main restricted universe multiverse

deb http://ubuntu.cn99.com/ubuntu/ precise-security main restricted universe multiverse

deb http://ubuntu.cn99.com/ubuntu/ precise-backports main restricted universe multiverse

deb http://ubuntu.cn99.com/ubuntu-cn/ precise main restricted universe multiverse

#电子科技大学

deb http://ubuntu.uestc.edu.cn/ubuntu/ precise main restricted universe multiverse

deb http://ubuntu.uestc.edu.cn/ubuntu/ precise-backports main restricted universe multiverse

deb http://ubuntu.uestc.edu.cn/ubuntu/ precise-proposed main restricted universe multiverse

deb http://ubuntu.uestc.edu.cn/ubuntu/ precise-security main restricted universe multiverse

deb http://ubuntu.uestc.edu.cn/ubuntu/ precise-updates main restricted universe multiverse

deb-src http://ubuntu.uestc.edu.cn/ubuntu/ precise main restricted universe multiverse

deb-src http://ubuntu.uestc.edu.cn/ubuntu/ precise-backports main restricted universe multiverse

deb-src http://ubuntu.uestc.edu.cn/ubuntu/ precise-proposed main restricted universe multiverse

deb-src http://ubuntu.uestc.edu.cn/ubuntu/ precise-security main restricted universe multiverse

deb-src http://ubuntu.uestc.edu.cn/ubuntu/ precise-updates main restricted universe multiverse

#中国科技大学

deb http://debian.ustc.edu.cn/ubuntu/ precise main restricted universe multiverse

deb http://debian.ustc.edu.cn/ubuntu/ precise-backports restricted universe multiverse

deb http://debian.ustc.edu.cn/ubuntu/ precise-proposed main restricted universe multiverse

deb http://debian.ustc.edu.cn/ubuntu/ precise-security main restricted universe multiverse

deb http://debian.ustc.edu.cn/ubuntu/ precise-updates main restricted universe multiverse

deb-src http://debian.ustc.edu.cn/ubuntu/ precise main restricted universe multiverse

deb-src http://debian.ustc.edu.cn/ubuntu/ precise-backports main restricted universe multiverse

deb-src http://debian.ustc.edu.cn/ubuntu/ precise-proposed main restricted universe multiverse

deb-src http://debian.ustc.edu.cn/ubuntu/ precise-security main restricted universe multiverse

deb-src http://debian.ustc.edu.cn/ubuntu/ precise-updates main restricted universe multiverse

#北京理工大学

deb http://mirror.bjtu.edu.cn/ubuntu/ precise main multiverse restricted universe

deb http://mirror.bjtu.edu.cn/ubuntu/ precise-backports main multiverse restricted universe

deb http://mirror.bjtu.edu.cn/ubuntu/ precise-proposed main multiverse restricted universe

deb http://mirror.bjtu.edu.cn/ubuntu/ precise-security main multiverse restricted universe

deb http://mirror.bjtu.edu.cn/ubuntu/ precise-updates main multiverse restricted universe

deb-src http://mirror.bjtu.edu.cn/ubuntu/ precise main multiverse restricted universe

deb-src http://mirror.bjtu.edu.cn/ubuntu/ precise-backports main multiverse restricted universe

deb-src http://mirror.bjtu.edu.cn/ubuntu/ precise-proposed main multiverse restricted universe

deb-src http://mirror.bjtu.edu.cn/ubuntu/ precise-security main multiverse restricted universe

deb-src http://mirror.bjtu.edu.cn/ubuntu/ precise-updates main multiverse restricted universe

#兰州大学

deb ftp://mirror.lzu.edu.cn/ubuntu/ precise main multiverse restricted universe

deb ftp://mirror.lzu.edu.cn/ubuntu/ precise-backports main multiverse restricted universe

deb ftp://mirror.lzu.edu.cn/ubuntu/ precise-proposed main multiverse restricted universe

deb ftp://mirror.lzu.edu.cn/ubuntu/ precise-security main multiverse restricted universe

deb ftp://mirror.lzu.edu.cn/ubuntu/ precise-updates main multiverse restricted universe

deb ftp://mirror.lzu.edu.cn/ubuntu-cn/ precise main multiverse restricted universe

#上海交通大学

deb http://ftp.sjtu.edu.cn/ubuntu/ precise main multiverse restricted universe

deb http://ftp.sjtu.edu.cn/ubuntu/ precise-backports main multiverse restricted universe

deb http://ftp.sjtu.edu.cn/ubuntu/ precise-proposed main multiverse restricted universe

deb http://ftp.sjtu.edu.cn/ubuntu/ precise-security main multiverse restricted universe

deb http://ftp.sjtu.edu.cn/ubuntu/ precise-updates main multiverse restricted universe

deb http://ftp.sjtu.edu.cn/ubuntu-cn/ precise main multiverse restricted universe

deb-src http://ftp.sjtu.edu.cn/ubuntu/ precise main multiverse restricted universe

deb-src http://ftp.sjtu.edu.cn/ubuntu/ precise-backports main multiverse restricted universe

deb-src http://ftp.sjtu.edu.cn/ubuntu/ precise-proposed main multiverse restricted universe

deb-src http://ftp.sjtu.edu.cn/ubuntu/ precise-security main multiverse restricted universe

deb-src http://ftp.sjtu.edu.cn/ubuntu/ precise-updates main multiverse restricted universe