Amorphous InAsSb films and hydrogenated InAsSb films are deposited on substrates of quartz glass and silicon by rf magnetron sputtering technique in different gas ambient. The effect of H addition on structure, optical properties and electrical properties of a-InAsSb is studied. It is found that the bonded hydrogen content increases with increasing H2 to Ar flow rate radio(R). When R is 0.1, Hydrogen addition shifts the optical absorption edge to higher energy, decreases the dark conductivity and improves the photo-sensitivity. However, hydrogen addition produces the crystallization of the film at R>0.1. Moreover the optical gap, dark conductivity and photo-sensitivity of the films have a reverse change compared with that in R=0. These results demonstrate that hydrogen has obvious passivation effects on rf sputtered amorphous InAsSb thin films only at R=0.1.