寫在前面：本文摘錄自網上，經過驗證，大膽使用。

一、ubuntu16.04更換國內源

1.備份原始原始檔source.list

桌面開啟終端，執行命令：sudo cp /etc/apt/sources.list /etc/apt/sources.list.bak

2.修改原始檔source.list

（1）終端執行命令：sudo chmod 777 /etc/apt/sources.list更改檔案許可權使其可編輯；

（2）執行命令：sudo gedit /etc/apt/sources.list開啟檔案進行編輯；

（3）刪除原來的檔案內容，複製下面的任意一個到其中並儲存（常用的是阿里源和清華源，推薦阿里源）；

阿里源：

deb http://mirrors.aliyun.com/ubuntu/ xenial main restricted universe multiverse
deb http://mirrors.aliyun.com/ubuntu/ xenial-security main restricted universe multiverse
deb http://mirrors.aliyun.com/ubuntu/ xenial-updates main restricted universe multiverse
deb http://mirrors.aliyun.com/ubuntu/ xenial-proposed main restricted universe multiverse
 

deb http://mirrors.aliyun.com/ubuntu/ xenial-backports main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ xenial main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ xenial-security main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ xenial-updates main restricted universe multiverse
 

deb-src http://mirrors.aliyun.com/ubuntu/ xenial-proposed main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ xenial-backports main restricted universe multiverse

3.更新

sudoapt-getupdate