The invention provides an air conditioner control method and system and an air conditioner. The air conditioner comprises an outdoor unit, a compressor and a throttling component. The control method comprises the steps that after the compressor is started, the throttling component is controlled to be adjusted to the preheating aperture for the first preset time; whether the air conditioner meets the preheating finishing condition or not is judged in real time; when the air conditioner meets the preheating finishing condition, the aperture of the throttling component is adjusted according to running parameters of the air conditioner; and when the air conditioner does not meet the preheating finishing condition, returning is conducted, and the throttling component is continuously controlledto be kept with the preheating aperture. According to the provided air conditioner control method, through adjustment of the aperture of the throttling component, the problem that in the air conditioner low-temperature heating start process in different environment temperatures, excessive liquid carrying is caused due to rapid heating start is effectively solved, and the air conditioner running reliability is improved.