An inducer installed before the inlet of pump impeller can efficiently resist the cavitation, however, it is lack of research in the fluid field about the variable pitch inducer at present. Based on CFD technical and Fluent program, the fluid field about variable pitch inducer was numerical simulated. Related to the example of the variable pitch inducer, in it, the distribution of velocity and pressure were taken out and the trace of the particle was plot and the main characteristics of the interior fluid field were described.