Abstract: This study systematically investigates the impacts of uncertainties in the form and the strength of the pairing force on observables related to nuclear fission, taking the neutron-induced fission of ²³⁹Pu as an example, thereby revealing the role of pairing in the fission process. The energy density functional theory (DFT) based on the Skyrme force was employed to calculate the potential energy surface in the two-dimensional deformation space of ²⁴⁰Pu, using volume, surface, and mixed pairing forces within the Hartree-Fock-Bogoliubov (HFB) approximation. And we also test the effects of varying pairing strengths for the mixed pairing force. Subsequently, based on the DFT calculations, the fission dynamics of ²⁴⁰Pu were further studied using the Time-Dependent Generator Coordinate Method (TDGCM) plus the Gaussian Overlap Approximation (GOA). By analyzing the influence of varying the types or the strength of the pairing force on fission related properties, we found that variation in the pairing strength significantly affect both small and large deformation regions. However, alterations in pairing force type primarily cause notable differences in the large deformation region. The configurations at large deformation in the nucleus have significant impacts on the fission dynamics. Our results show that there are explicit differences in the configurations at large deformations obtained by different types of pairing force, so the choice of pairing force is very important for the fission description. The mixed-type of pairing force gives the best results in the calculation of fission dynamics.