Abstract: Considering overly restrictive conditions of system reliability modelling with exponential distribution and other typical distributions in previous studies, a highly descriptive system reliability model is constructed utilizing the phase-type (PH) distribution, which has the ability to fit any distribution approximately, for an N component warm standby repairable system that has only a single repair platform. Assuming that the life and repair time of operating and standby components are subject to different PH distributions, expressions are obtained for a series of reliability parameters including system steadystate availability, mean time between failures of the system, and failed unit arrival rate of the repair platform. Finally, example analysis is performed to verify the correctness and applicability of this approach.