Abstract: Based on some relative papers’ models, a novel CNT film with high optical transmittance and strongelectromagnetic shielding in broadband is designed and simulated. By changing the thin film’s structure parameters forsimulation and summarized the regularity of the results, an optimum model is obtained. The simulation results show that thethin film’s optical transmittance is higher than 90%, among 600~900THz is even higher than 95%, and the shielding effectiveness (SE) is 78dB at 20GHz, 84dB at 10GHz, respectively. Currently, this experimental result is better than otherrelatively published papers’ data. Moreover, electromagnetic wave’s oblique incidence into the film is simulated and analyzed.It can set a experimental foundation for the thin film’s further application on freeform optics field.