Addressing the issues of traditional single-stage heat pumps whose efficiency deteriorates rapidly with increased temperature requirements and the significant energy waste caused by direct discharge of residual heat from auxiliary condensers, this work proposes a Heat Recovery Flash Evaporation Cascade Heat Pump Drying System (HR-FCHP) that leverages the benefits of low-temperature drying in the early stages of the process to enhance the external quality of materials. By incorporating the characteristics of a two-stage compression heat pump, this system couples the auxiliary condenser heat recovery with cascaded temperature drying. A thermodynamic model is established and validated using data from published literature. And a comprehensive thermodynamic analysis of the system is conducted to investigate the influence of key parameters on the operational efficiency of the proposed HR-FCHP system. Simultaneously, the proposed system is compared with a single-stage heat pump drying system (SSHP), a basic cascaded heat pump drying system (FCHP), and a parallel condenser heat pump drying system (PCHP) under the same operating conditions. To facilitate the validation of the energy-saving and drying efficiency of the proposed HR-FCHP system, an additional auxiliary condenser heat dissipation subsystem is incorporated into the three comparative heat pump subsystems, all of which feature a closed drying subsystem. This subsystem aims to recover and utilize excess heat for pre-drying the drying materials. The results indicate that the proposed HR-FCHP system has higher energy-saving and drying efficiency compared to the SSHP, FCHP, and PCHP systems. The coefficient of performance for heating (COPh) and specific moisture extraction rate (SMER) of HR-FCHP system are 5.40 and 4.31 kg/kWh, which are 53.85% and 65.77%, 33.00% and 20.73%, and 7.14% and 9.40% higher than the COPh and SMER of the SSHP, FCHP, and PCHP systems, respectively. Additionally, the HR-FCHP system has the lowest initial cost (CIC) at 66400 CNY, and its life cycle cost (CLCC) can be reduced by 69.86%, 40.92%, and 8.57% compared to SSHP, FCHP, and PCHP systems, respectively. This novel heat pump drying system can serve as a theoretical foundation for future experimental research and practical applications.