The direct contact condensation (DCC) is a significant phenomenon in nuclear reactor and its balance facilities, together with other chemical engineering systems. DCC occurs when the vapor is injected into the subcooled water, contacts and condenses on the interface directly. The DCC phenomenon accompanied with the heat transfer and mass transfer will result in the temperature and pressure fluctuations in the tank. This paper discusses the DCC in the subcooled water tank from the view of computation fluid dynamics. The numerical simulation was performed with the CFD software, Fluent, in which the direct contact condensation phenomenon was modeled with the Euler-Euler framework for two phases flow, and the evaporation & condensation model was adopted to simulate the mass transfer process. During the simulation process, the flow field and temperature field are derived. In addition, the shape and size of plume jet are also investigated.