在终端试试这个:

/usr/local/bin/mysql_secure_installation

如果你忘记了你的密码或者想把它改成你的MySQL:

Start your terminal and enter: sudo su Enter the password for you system Stop your MySQL server: sudo /usr/local/mysql/support-files/mysql.server stop Leave this window open, run second terminal window and enter here: mysql -u root And change your password for MySQL: UPDATE mysql.user SET authentication_string=PASSWORD('new_password') WHERE User='root'; where "new_password" - your new password. You don't need old password for MySQL. Flush, quit and check your new password: FLUSH PRIVILEGES; Close all windows and check your new password for MySQL.

在新的MySQL 5.7版本中，由于某些原因MySQL的二进制命令没有附加到shell中，你必须这样做:

安装完成后重新启动Mac。 MySQL开始: System Preferences→MySQL→Start按钮 进入终端的MySQL install文件夹: cd /usr/local/mysql/bin/ 访问MySQL: ./mysql -u root -p 并输入为安装提供的初始密码。 在MySQL客户端修改密码: mysql> ALTER USER 'root'@'localhost' IDENTIFIED BY 'MyNewPassword'

现有答案中提到的方法不适用于MySQL 5.7.6或更高版本。根据MySQL文档，这是推荐的方法。

B.5.3.2.3重置Root用户密码:通用说明

MySQL 5.7.6及以上版本:

mysql> ALTER USER 'root'@'localhost' IDENTIFIED BY 'MyNewPass';

参考:https://dev.mysql.com/doc/refman/5.7/en/resetting-permissions.html

当您登录MySQL终端时，请尝试执行FLUSH PRIVILEGES命令。如果这不起作用，请在MySQL终端中尝试以下命令集

mysql -u root

mysql> USE mysql;
mysql> UPDATE user SET password=PASSWORD("NEWPASSWORD") WHERE User='root';
mysql> FLUSH PRIVILEGES;
mysql> quit

用你想要的任何密码更改NEWPASSWORD。应该都准备好了!

更新:从MySQL 5.7开始，密码字段被重命名为authentication_string。修改密码时，使用以下查询来修改密码。所有其他命令保持不变:

mysql> UPDATE user SET authentication_string=PASSWORD("NEWPASSWORD") WHERE User='root';

请不要使用MySQL 8.0+

mysql> UPDATE mysql.user SET authentication_string='password' WHERE User='root'; 

因为它覆盖了authentication_string，它应该是一个哈希而不是纯文本，而是使用:

mysql> `ALTER USER 'root'@'localhost' IDENTIFIED BY 'MyNewPass';` 

mysql网站上提供的说明非常清楚，比上面提到的还要清楚

$ sudo /usr/local/mysql/support-files/mysql服务器停止 $ sudo /usr/local/mysql/support-files/mysql服务器启动——skip-grant-tables /usr/local/mysql/bin/mysql mysql> FLUSH PRIVILEGES; mysql> ALTER USER 'root'@'localhost' IDENTIFIED BY 'MyNewPass'; mysql>退出或按Ctrl + z $ sudo /usr/local/mysql/support-files/mysql服务器停止 $ sudo /usr/local/mysql/support-files/mysql服务器启动 /usr/local/mysql/support-files/mysql -u root -p 输入新密码，即MyNewPass

参考:http://dev.mysql.com/doc/refman/5.7/en/resetting-permissions.html