The kinetic parameters of in-hospital neutron irradiator mark 1 (IHNI-1) reactor, effective delayed neutron fraction and neutron generation time are calculated by CKPWC（calculating kinetic parameters based on WIMS and CITATION）program based on the calculated results of WIMS and CITATION. The cell homogenized cross section and 69-group flux density are calculated by WIMS. Flux density and adjoint flux density are obtained based on 4-group diffusion calculation using CITATION. The kinetic parameters are calculated by CKPWC based on the results of WIMS and CITATION. The analysis based on the calculation indicates that the energy group structure has a significant effect on the result of kinetic parameter. An appropriate energy group structure is given in this paper. To verify the accuracy of the method, Xi’an Pulsed Reactor is benchmarked and the result is corresponded to its design value.