mysqlshow -u root mysql

[admin]

I have make up mysql in my win2000.And I have put this command:
c:\mysql\bin>mysqlshow
+-----------+
| Databases |
+-----------+
| mysql |
| test |
+-----------+
c:\mysql\bin>mysqlshow -u root mysql
mysqlshow: Access denied for user: 'root@localhost' (Using password: NO)

what means is it ? How to settle this problem?