The active jet method on the suction surface of the hydrofoil can well control the cavitation flow around the hydrofoil and reduce the occurrence and development of cavitation. Therefore, based on the method of active jet, with the density-corrected SST k-ω turbulence model and the Zwart-Gerber-Belamri cavitation model, the effect of jet parameters on the flow characteristic of cloud cavitation around the NACA66 (MOD) hydrofoil was numerically studied. According to the orthogonal design method, under the condition of incoming flow Re=5.07×105, the angle of attack α=8°, and the cavitation number σ=0.83, by studying 16 groups of jet structures composed of different jet parameters, the influence of the jet position, jet angle and jet flow rate on the cavitation and hydrodynamic performance of the flow field around the hydrofoil was evaluated, and the optimal jet parameters were obtained. The results showed that the jet position had the greatest influence on the suppression of cavitation flow, and the jet angle had the maximum influence on the hydrodynamic performance. Using the optimal jet parameters can reduce the time-averaged dimensionless cavitation area by 46.57% and increase the time-average lift-drag ratio by 5.59% in the hydrofoil cavitation flow field. At this point, the injected jet in the downstream direction collided with re-entrant jet torwards the leading edge, which formed strong mixing and significantly consumed the momentum of the re-entrant jet, thereby preventing the re-entrant jet from continuing to move to the leading edge of the hydrofoil, greatly weakening the destabilizing shedding of attached cavitation.