The rotating ramjet is a new conceptive engine based on the ram-compressed technology rely on high-speed rotating rotor, the engine’s core component is an internal combustion rotor, which has the functions of compressing air, combusting and doing work by exhausting. In order to predict the combusting flow field in Ram-compressed Rotor chamber, the model of Ram-compressed Rotor was set up. The fuel composition was defined in software prePDF. Realizable was used for the gas phase turbulence. Fuel particles phase makes use of stochastic tracking model. The Structure characteristics of the combusting flow field and temperature field were found out by numerical simulation. The numerical simulation results show that the combusting flow field in the Ram-compressed Rotor Chamber has simple inlet and outlet is well, and offer the references to the design of combustion chamber especially the contour design of the scramjet nozzle.