The study focuses on a duck shed located in North China with the heat load index of 218 W/m2. A solar-air dual-source heat pump system with phase change heat storage (SAHP-PC) was designed, and optimized in TRNSYS simulation. The results show that the optimal conditions are: setting solar collectors to half of the heating area, matching per unit area collector with 20L water tank, and controlling the splitting ratio of water-source heat pump to air-source heat pump at 7:3. Then the COP of water-source heat pump reaches 5.05, the solar fraction is 62%, corresponding to an energy-saving rate of 23%.