Three to five people. The number of 3-5 evaluation experts has reached a balance point in the coordination among experts and the utilization of resources, which can ensure the scientificity and fairness of evaluation. Too many evaluation experts will increase the difficulty of coordination among experts, which will lead to complicated evaluation process and increase the evaluation cost and cycle, while too few evaluation experts will easily lead to evaluation deviation, which will make it impossible to evaluate the project comprehensively and accurately.