MySQL server is not starting

Error massage :
[ERROR] /usr/sbin/mysqld: Can't find file: './mysql/host.frm' (errno: 13)
140329  5:47:35
[ERROR] Fatal error: Can't open and lock privilege tables: Can't find file: './mysql/host.frm' (errno: 13)

Solution:  Please change ownership of MySQL root folder

chown -R mysql:mysql /var/lib/MySQL

and restart MySQL service