This heating system has a heat medium flow path which is configured such that a heating terminal for exchanging heat between the air in a space to be air-conditioned and a heat medium, a circulation pump for applying pressure to the heat medium, and a heating device for heating the heat medium are connected by pipes to circulate the heat medium therein. This heating system comprises: a delivery temperature sensor that detects a delivery heat medium temperature which is the temperature of the heat medium flowing from the heating device to the heating terminal; a return temperature sensor that detects a return heat medium temperature which is the temperature of the heat medium flowing from the heating terminal to the heating device; a room temperature sensor that detects a room temperature which is the temperature in the space to be air-conditioned; and a control device that controls the heating device and the circulation pump. The control device controls the rotational speed of the circulation pump on the basis of the temperature difference between the return heat medium temperature and the room temperature and the deviation between the delivery heat medium temperature and a preset target delivery heat medium temperature.