An outdoor unit of an air-conditioning apparatus is provided with an outdoor heat exchanger configured to cause refrigerant that flows in the outdoor heat exchanger and air to exchange heat with each other, a plurality of outdoor fans each configured to rotate by driving of a motor and send air to the outdoor heat exchanger, and a controller configured to control the driving of the motor. When operation of one of the plurality of outdoor fans is stopped, the controller is configured to control the motor such that a rotation frequency of each of the plurality of outdoor fans that is in operation after operation of the one of the plurality of outdoor fans is stopped is higher than a rotation frequency of each of the plurality of outdoor fans that is in operation before operation of the one of the plurality of outdoor fans is stopped.