The invention discloses a control method and an air conditioner under a heating mode of the air conditioner. The control method includes the steps that S10, whether launch condition of the temperaturecompensation is met is determined; S20, under the situation of meeting the launch condition, the temperature compensation of a T from an indoor environment temperature detection result iscarried out, and the T after correcting the indoor environment temperature is obtained, wherein the T minus the T is equal to the T, and the T is compensation dosage of the temperature compensation; and S30, the running state of a compressor is controlled by the T correction after revising the indoorenvironment temperature. When the air conditioner is running in the heating mode and it is ensured that the launch condition of the temperature compensation is met, the indoor environment temperaturecompensation is carried out according to the operating condition of the air conditioner, and the influence of hot air floatation and other factors on the indoor environmental temperature detection result is eliminated, so that the comfort experience of air conditioner in the heating mode is improved.