The lattice Boltzmann method, combined with the boundary layer model and the very large eddy simulation method, was used to simulate the MIRA notchback model to obtain an accurate unsteady flow field and a more reliable mean flow field. Based on the analysis of the tail flow state, jet holes were set up at the model tail. To analyze the effects of different jet states on the aerodynamic performance, constant jet method was used to explore the optimal values of blowing and sucking conditions, jet hole diameters and jet velocities at each position. The numerical results indicate that setting up the jet scheme can reduce the drag coefficient by inhibiting the longitudinal vortex and improving the wake structure of the model. A case of single jet placing jet holes at the bottom of the rear windshield can achieve 10 % drag reduction.