The invention discloses a solar-aided, air-source, trans-critical CO2 heat pump integrated air-conditioning system, belonging to the field of solar energy utilization and air conditioning technique, comprising CO2 heat pump (refrigerating) system, solar heat collecting system, indoor heat exchange system and outdoor heat exchange system, interconnected through three-way and four-way valves according system operation path. And for different weather conditions in the four seasons, it can adopt the five operating modes of heating, refrigeration, hot water, heating + hot water, and refrigeration + hot water, implementing hot water, cold and heat supply; besides, by adopting CO2 as heat pump (refrigeration) working medium, it has advantages of high efficiency, saving energy and environmental protection, compactness, and low operation cost.