[root@localhost ~]# mysql -u root -p
mysql> use mysql
mysql> update user set password=password("newpassword"); //修改密码
mysql> quit
重启mysql服务：
# /etc/init.d/mysqld restart
[root@localhost ~]# mysql -u root -p
mysql> use mysql
mysql> update user set password=password("newpassword"); //修改密码
mysql> quit
重启mysql服务：
# /etc/init.d/mysqld restart