1、如果知道root密码：
mysql -u root -p
输入密码
use mysql;
UPDATE user SET Password = PASSWORD(‘newpass‘) WHERE user = ‘root‘;
FLUSH PRIVILEGES;
quit;
2、如果不知道密码
service mysqld stop;
mysqld_safe --skip-grant-tables&mysql -u root mysql;UPDATE user SET password=PASSWORD("new password") WHERE user=‘root‘;FLUSH PRIVILEGES;FLUSH PRIVILEGES;原文：https://www.cnblogs.com/hy87/p/9860649.html