Objective To wear common dental alloy materials against tooth hard tissues, and compare the vertical substance loss of enamel and dentin. Methods Four dental alloy materials (soft Co-Cr alloy, gold alloy 55.6%, Co-Cr alloy and titanium alloy) were selected, and were worn against human in vitro enamel and dentin specimens with paired grouping procedures. The vertical substance loss of enamel and dentin was quantified as wear depth, and was statistically analysed. The worn surface areas were observed by stereo microscope. Results The values of wear depth of enamel specimens against soft Co-Cr alloy, gold alloy 55.6%, Co-Cr alloy and titanium alloy were (54.37±6.91) μm, (24.77±4.49) μm, (127.74±16.25) μm and (57.79±7.39) μm respectively, and those of dentin specimens were (167.76±18.23) μm, (44.32±9.21) μm, (171.39±20.79) μm and (86.04±11.49) μm respectively. Statistical analysis revealed that the vertical substance loss of tooth tissues in wear against gold alloy 55.6% was significantly less than that in wear against soft Co-Cr alloy (P<0.000 1), and the vertical substance loss of tooth tissues in wear against titanium alloy was significantly less than that in wear against Co-Cr alloy (P<0.000 1). Conclusion In common fixed dental prostheses materials, gold alloy 55.6% wears less than soft Co-Cr alloy against tooth hard tissues. In common movable dental prostheses materials, titanium alloy wears less than Co-Cr alloy against tooth hard tissues.