The invention belongs to the field of air conditioners, and specifically provides a control method of the air conditioner under refrigeration conditions. Under the existing refrigeration conditions, when the indoor temperature of the air conditioner reaches the user's habitual temperature, the indoor humidity is quite different from the user's habitual humidity. The control method of the present invention includes: acquiring the preset startup time of the air conditioner and the outdoor ambient temperature, Correct the preset startup time, determine the air conditioning time, determine the advance startup time, obtain the actual indoor temperature T and actual humidity RH, and calculate the indoor dew point temperature T es , based on user habit information, compare T and T s size, and RH vs. RH s size, based on comparison results and dew point temperature T es , control the frequency of the compressor, the opening of the throttling device, and the wind speed of the indoor fan, so that T p with T es fit. The present invention can control the degree of refrigeration and the degree of dehumidification, so as to make T reach T s , RH has also reached RH s The standard also makes the early opening time more accurate.