Grid Computing receives growing attention from scientists and scholars these years, of which Grid Information Service is the highlight and one of the most difficult subjects. Grid Information Service is characterized in its wide distribution, high fault tolerance, and dynamic functions as well as diversified forms. As the foundation and core of the Grid Information Service, the distributed database of LDAP (Light weight Directory Access Protocol) has been widely used so far. In order to make the system more effective and efficient, this paper puts forward the strategies of Ring replication and Thread replication, both of which are really better ways to raise the efficiency of the Grid Information Service System compared with many other replication strategies.