AgSnO2 contact materials with different SnO2 contents were prepared by powder metallurgy,and the effect of SnO2 content on the arc behavior of AgSnO2 contact materials was studied.The erosion surface morphology of AgSnO2 contact materials were characterized by scanning electron microscope,and the factors which affect arc erosion were discussed as well.The results shows that the arc erosion prefer to occur on SnO2 particles.The increased SnO2 content decreases the erosion area and deepens the erosion pits significantly,and,thus,has an obvious molten metal splash.