Abstract: Based on life cycle assessment（LCA） method,the input of materials and energy,environmental impact,total energy consumption and energy payback time in the whole life cycle of 32 kW ORC system with Al₂O₃/R141 b nanorefrigerant as working medium are calculated,three aspects such as contribution,sensitivity and improvement are analysed.Finally,the environmental impacts of different power generation systems are compared.The results show that the total energy consumption in the whole life cycle of 32 kW ORC system using Al₂O₃/R141 b nanorefrigerant as working medium is 24360.4951 MJ,the energy payback time only accounts for 1.03% of the whole life cycle.The main stage that affects the environment in the life cycle of ORC system is the production of ORC system,during the production stage,the environmental impact of ORC system components is the greatest.The main direction of reducing the environmental load is to optimize the working condition of the system,improve the structure of the components and search for nanorefrigerant with better heat transfer performance.The environmental advantages of ORC system using nanorefrigerant as working medium are clarified.