An air-conditioning apparatus is configured to melt a large amount of adhering frost while maintaining an appropriate operation of a compressor by setting a defrosting operation time period depending on a low pressure of the compressor. The air-conditioning apparatus includes a refrigerant circuit including the compressor, a refrigerant flow switching device, a heat source-side heat exchanger, an expansion device, and a use-side heat exchanger, which are connected via a refrigerant pipe to form a refrigeration cycle, a pressure sensor configured to detect a pressure on a suction side of the compressor, and a controller configured to control, in a defrosting operation, the refrigerant flow switching device to supply compressed refrigerant from the compressor to the heat source-side heat exchanger, compare a value detected by the pressure sensor with a first threshold value, and change the defrosting operation time period based on a result of the comparison.