Abstrac t--Geographical knowledge grid is a platform which utilizes grid computing technology and geo-information science to supply powerful spatial knowledge discovery and sharing ability. Due to the complexity of knowledge grid, we design a portal named as GeoKS-Grid Portal as the access point to the platform. This paper describes the design and development procedures and introduces the framework of the portal, which consists of data sharing and management module, platform monitoring module, grid task execution module, geographical knowledge service module and portal administration module. This paper also displays the application of the portal in air pollution dispersion simulation of Xiamen City.