As a web-based application，Grid Portal makes end-users to access the functions and services of Grid easier. The new generation of the Grid Portal bases on Portlet. The Portlet is visual modules which reduce the difficulty and the cost of the Grid Portal development significantly. Moreover, Portlet makes different portals highly compatible and easy migrating. Now the Portlet-based Portals became the mainstream of the new generation of Grid Portal. In this paper the development and the framework design of the Portlet-based Portals were introduced. Then the functions and design of the Grid portal in the YangBaJing cosmic ray observation experiment were discussed.