The traditional PID controller is used to control the core power, which has the problems of large overshoot and long regulating time in the control process. In order to solve this problem, based on the core transfer function model, the PD controller, the PID controller and the fuzzy controller are weighted and switched by T-S fuzzy rules, and T-S fuzzy switching controller is designed. Taking the core power control of a lead cooled fast reactor as an example, a T-S fuzzy switching control system of the core power is established to simulate the relative power setpoint value step and the core inlet coolant temperature disturbance. The results show that the T-S fuzzy switching controller designed based on the core transfer function model can achieve a good control of the core power.