Considering the non-equilibrium heat transfer characteristics between electrons and lattices in the process of laser heating, a two-step lattice Boltzmann method (LBM) equation is established by combining the LBM and the two temperature model. Then the thermal response characteristic of a nano-film irradiated by the short-pulse laser is simulated using this method. The change law of temperature distribution in thin film with time and space is analyzed in the irradiation process. In addition, the effects of the laser intensity and the thin film thickness on the thermal response are also discussed. The results show that there exists a significant hysteresis phenomenon between the changes of the lattice temperature and the electron temperature in the irradiation process, and the calculated electron temperature response and damage thresholds are agree well with the experimental results. Those indicate that the proposed two-step LBM equation can describe the non-equilibrium heat transfer phenomenon between electrons and lattices in the process of the laser irradiation well. It is also found that with the enhancement of the laser energy and the decrease of the film thickness, the electron and lattice temperatures of the film surface are significantly increased, and the time at which the electron and the lattice temperature achieve stability are also delayed.