Abstract: Cloud computing for e-government application development provide effective support platform,can help to solve the problems in three aspects:safety,performance and cost.In this paper,we proposed a infrastructure of ISeM over Cloud to realize SaaS application which contains five layers:service tenant and contributor，task management,task pool,task execution and database layer.We model the system services and tasks as OWL classes,and describd the mechanism to decompose the task to fundamental services and dispatch them.System has been implemented based hadoop platform.With ISeM Cloud,we need not to deploy the system to each department.It decreased expenses on the hardware platform and the system maintenance.