In an air-conditioning apparatus, a heat source side heat exchanger 12, intermediate heat exchangers 15a and 15b, and use side heat exchangers 26a to 26d are separately formed and adapted to be disposed at separate locations, respectively. There are provided a defrosting operation function to melt frost attached around the heat source side heat exchanger 12, and a heating function during defrosting operation that drives a pump 21a to circulate a heat medium and supply heating energy to the use side heat exchangers 26a to 26d in need of heating to perform heating operation. The defrosting operation function can be executed by switching a four-way valve 11 to cooling side to introduce a high-temperature high-pressure refrigerant flowed out of the compressor 10 into the heat source side heat exchanger 12.