方法1： 用SET PASSWORD命令

mysql -u rootmysql> SET PASSWORD FOR 'root'@'localhost' = PASSWORD('newpass');

方法2：用mysqladmin

mysqladmin -u root password "newpass"如果root已经设置过密码，采用如下方法mysqladmin -u root password oldpass "newpass"

方法3： 用UPDATE直接编辑user表

mysql -u rootmysql> use mysql;mysql> UPDATE user SET Password = PASSWORD('newpass') WHERE user = 'root';mysql> FLUSH PRIVILEGES;

方法4: 在丢失root密码的时候，可以这样

mysqld_safe --skip-grant-tables&mysql -u root mysqlmysql> UPDATE user SET password=PASSWORD("new password") WHERE user='root';mysql> FLUSH PRIVILEGES;