The influence of the sliding velocity and atmospheric temperature on the specific wear amount of polyoxymethylene was evaluated with the ring-on-ring apparatus. The specific wear amount showed the variation of S-character type with maximum value, according to the change in the sliding velocity and the atmospheric temperature. When those results are plotted according to the sliding Surface temperature, they have been found to be arranged as the same dependence. The specific wear amount of polyoxymethylene was assumed to be proportional to the product of actual contact area and reciprocal of the fracture energy. Then, the temperature dependency of the product of the fracture energy, calculated from stress-strain curve, and the actual contact area, calculated from Hertz's equation with elastic modulus, was able to explain the sliding Surface temperature dependency of the specific wear amount well. (c) 2006 Wiley Periodicals, Inc.