Lanthanum hexaboride films were deposited on SiO₂ substrates in a vacuum chamber by D.C. magnetron sputtering from Lanthanum hexaboride pellet target. The films deposited with the same parameters besides the argon pressure. XRD, AFM and style profiler were used to characterize the properties of the deposited films. Surface of the films was compactive and smooth. Density of the film increased with the argon pressure. Roughness of the films decreased firstly and increased after with increasing of the argon pressure. Structure of the films was studied by the XRD. Results of the XRD showed that the dominant crystal face was (100) face. The crystallinity decreased with the increased argon pressure. Deposition rate of the film increased first and decreased last, and the value was lager than other at the argon pressure of 1.5Pa.