Abstract: Dry sliding wear tests were performed for a H13 steel at room temperature (RT), 200 and 400 ℃ as well as various loads on a pin-on-disk wear tester. The wear behavior and mechanisms under various testing conditions were studied. The results showed that the wear rate of H13 steel increased in a sequence of 200 ℃, RT, 400 ℃. At room temperature, wear rate increased with the increasing load and adhesive wear prevailed due to inadequate tribo-oxide on the worn surface. At 200 ℃,increasing load from 50 to 100 N reduced the wear rate due to the formation of tribo-oxide layer on worn surfaces. As the load increased from 100 to 200 N, wear rate slightly increased, and was substantially lower than that at RT and 400 ℃. In this case, mild oxidative wear prevailed. At 400 ℃, the wear rate increased with the increasing load. This is the result of load induced plastic deformation or/and thermal softening, and delamination. At a load higher than 150 N, the wear rate of H13 steel rapidly increased and severe wear occurred. The wear mechanism was oxidative wear and plastic extrusion.