Abstract: The simple, high inherent safety and economy multi-application reactors are necessary to fulfill the future requirements of the small nuclear power supply, nuclear heating supply, hydrogen production, seawater desalinization, and so on. A multi-application integrated light water reactor was proposed, including primary design characteristics and parameters. The safety analysis was calculated using the RELAP5 code, which focused on the loss of coolant accident (LOCA) and loss of flow accident (LOFA). The results show that the inherent characteristic and safety system can ascertain the reactor being under the coolant water on the conservative assumption. The passive residual heat removing system can remove the decay heat effectively. It is the foundation for the further development.