The aim of this paper is the study of the tribological behavior of DLC-coated 100C6 couple vs. temperature. The DLC coatings studied belong to amorphous hydrogenated carbon coatings. The goal of this study is to characterize the friction coefficient evolution after 1 h tests vs. sliding velocity and contact pressure for several test temperature values. Tests were carried out for the pin-on-disc configuration under three normal loads, three sliding velocities and for test temperatures between room temperature and 400 degreesC. Results have shown that the DLC-coated 100C6-steel discs should not be used at temperatures higher than 200degreesC. Coating damage strongly increases with high test temperature mainly due to stiffness reduction of 100C6-steel substrate. (C) 2003 Elsevier Science B.V. All rights reserved.