The intense D-T neutron generator is one of the ideal neutron sources for BNCT, and its neutron intensity still needs to be improved. One of the core factors restricting the yield increase of the neutron generator is the cooling problem of its rotating target system. In the research and development of the intense neutron generator, the cooling effect of the target system should be evaluated thoroughly. This study used the fluent code to simulate the influence of different system parameters such as cooling water flow rate and cooling water temperature on the heat transfer process of the rotating target. And it discussed the optimization of the heat dissipation effect of the rotating target by the schemes of adding radiators, changing coolants and substrate materials. In this system, using diamond as the substrate material of the target has a better heat dissipation effect than using copper. Using liquid nitrogen as a coolant has a better heat dissipation effect than using water. The cooling effect also has some improvement after adding heat sinks, and at the same monitoring points, the neutron count of the target with heat sinks is slightly higher than that of the target without heat sinks. The target equipped with three-layer superimposed heat sinks and with diamond as the backing can meet the requirements of the cooling system for the neutron generator with 1012 n/s.