Abstract The dependence of the crystalline quality of C 60 films on helium gas pressure is investigated by means of X-ray diffraction measurements. The results show that perfectly (111) oriented crystalline C 60 films with large grains are successfully deposited on synthetic 1 M phlogopite mica-fluorophlogopite (001) plane at the substrate temperature of 433 K when the helium gas pressure is 2.667 × 10 −2 Pa. We suggest that under appropriate helium gas pressure, the energy change of C 60 molecules through collisions with helium atoms and the decrease of the supersaturation of the vapor pressure in the vicinity of the substrate result in a quasi-thermodynamic equilibrium deposition system, which ensures the formation of high quality crystalline C 60 films on (001) plane of the fluorophlogopite substrate.