The main drawback of any Design for Reliability methodology is lack of easy accessible reliability models, prepared individually for each critical component. In this paper, a reliability model for SiC power MOSFET in SOT -227B housing, subjected to power cycling, is presented. Discussion covers preparation of accelerated lifetime test required to develop such reliability model, analysis of semiconductor degradation progress, samples post-failure analysis and identification of reliability model parameters. Such model may be further used for failure prognostics or useful lifetime estimation of high performance power supplies.