Q. What is my root password for MySQL under CentOS Linux 5.0 server?
A.. There is no default password (empty password) for MySQL database server. You need to assign root password after installing MySQL via yum / rpm command.
Some admin set the root password same as the server root password.
If you are using special control panel software such as Plesk then use "admin" and the admin password. Use mysql command to connect to mysql server.
You can alway reset forgotten mysql root password.