In support of NASA’s Propulsion and Cryogenic Advanced Development (PCAD) project, a liquid oxygen (LO2)/liquid methane (LCH4) Integrated Propulsion System Test Bed (IPSTB) was designed and advanced to the Critical Design Review (CDR) stage at the Johnson Space Center. The primary objectives of the IPSTB are to study LO2/LCH4 propulsion system steady state and transient performance, operational characteristics, and to validate fluid and thermal models of a LO2/LCH4 propulsion system for use in future flight design work. Two phase thermal and dynamic fluid flow models of the IPSTB were built to predict the system performance characteristics under a variety of operating modes and to aid in the overall system design work. While at ambient temperature and simulated altitude conditions at the White Sands Test Facility, the IPSTB with its approximately 600 channels of system instrumentation is designed to operate under a variety of integrated main engine and reaction control engine duty cycles. The pressure, temperature, and flow rate data collected during this testing is planned to validate analytical models of the IPSTB’s thermal and dynamic fluid flow performance. An overview of the IPSTB design and analytical model development will be presented. Nomenclature