使用mysql5.5，突然root密码忘记，怎么也登录不了，很急人，该怎么解决呢？下面通过本文给大家介绍mysql5.5忘记root密码的解决办法，需要的朋友参考下吧

方法一：

操作系统：windows操作系统，xp或win7.

C:UsersAdministrator>cd C:Program FilesMySQLMySQL Server 5.5bin

C:Program FilesMySQLMySQL Server 5.5bin>net stop mysql

MySQL 服务正在停止.

MySQL 服务已成功停止。

C:Program FilesMySQLMySQL Server 5.5bin>mysqld --skip-grant-tables

你会看到窗口光标在下一行的第一个位置闪烁，这说明已经启动了，不需要管。

新建一个命令行窗口同样进入到e:mysql5.5bin目录，启动mysql

C:Program FilesMySQLMySQL Server 5.5bin>mysql Welcome to the MySQL monitor. Commands end with ; or g. Your MySQL connection id is 1 Server version: 5.5.36 MySQL Community Server (GPL) Copyright (c) 2000, 2014, Oracle and/or its affiliates. All rights reserved. Oracle is a registered trademark of Oracle Corporation and/or its affiliates. Other names may be trademarks of their respective owners. Type 'help;' or 'h' for help. Type 'c' to clear the current input statement. mysql> show databases; +--------------------+ | Database | +--------------------+ | information_schema | | mysql | | performance_schema | | test | +--------------------+ 4 rows in set (0.00 sec) mysql> use mysql; Database changed mysql> update user set password=PASSWORD('oracle') where user='root'; Query OK, 2 rows affected (0.00 sec) Rows matched: 2 Changed: 2 Warnings: 0 mysql> flush privileges; Query OK, 0 rows affected (0.01 sec) mysql> quit Bye

看看那任务管理器中是否有mysqld.exe进程，如有，kill .

C:Program FilesMySQLMySQL Server 5.5bin>net start mysql

MySQL 服务正在启动 .

MySQL 服务已经启动成功。

C:Program FilesMySQLMySQL Server 5.5bin>mysql -uroot -poracle Welcome to the MySQL monitor. Commands end with ; or g. Your MySQL connection id is 1 Server version: 5.5.36 MySQL Community Server (GPL) Copyright (c) 2000, 2014, Oracle and/or its affiliates. All rights reserved. Oracle is a registered trademark of Oracle Corporation and/or its affiliates. Other names may be trademarks of their respective owners. Type 'help;' or 'h' for help. Type 'c' to clear the current input statement. mysql>

方法二：

操作系统：windows操作系统，xp或win7.

1.dos命令行窗口 进入e:mysql5.5bin ,停止mysql 服务

e:mysql5.5bin>net stop mysql

注意:看看那任务管理器中是否有mysqld.exe进程，如有，kill them all.

2. 以不检查权限的方式启动mysql

e:mysql5.5bin>mysqld.exe --skip-grant-tables

你会看到窗口光标在下一行的第一个位置闪烁，这说明已经启动了，不需要管。

3. 新建一个命令行窗口同样进入到e:mysql5.5bin目录，启动mysql

e:mysql5.5bin>mysql

4. 修改root密码

mysql>use mysql mysql>update user set password=PASSWORD('new_password') where user='root'; mysql>flush privileges; mysql>quit

5. 看看那任务管理器中是否有mysqld.exe进程，如有，kill them all.

6. 重启mysql，就可以用你设置新密码登陆

e:mysql5.5bin>net start mysql e:mysql5.5bin>mysql -u root -pnew_password that's all .