An air conditioner heating mode control method, characterized in that it includes: obtaining an indoor temperature and comparing the indoor temperature with a first indoor temperature threshold as an air conditioner running at the heating mode; performing a dual PID control process if the indoor temperature is less than or equal to the first indoor temperature threshold; wherein the dual PID control process including: calculating the difference between the indoor temperature and a set indoor target temperature to obtain a indoor temperature difference; performing a PID calculation according to the indoor temperature difference to obtain a first target frequency; obtaining a coil temperature of an indoor unit heat exchanger; calculating the temperature difference between the coil temperature and a coil target temperature to obtain a coil temperature difference; performing a PID calculation according to the coil temperature difference to obtain a second target frequency; comparing the first target frequency obtained in the indoor temperature PID calculation with the second target frequency obtained in the coil temperature PID calculation; and performing a frequency control on the compressor in which the greater one between the first target frequency and the second target frequency is used as the target frequency; wherein the coil target temperature is determined according to the indoor temperature, wherein the coil target temperature is negatively correlated with the indoor temperature. obtaining an indoor temperature and comparing the indoor temperature with a first indoor temperature threshold as an air conditioner running at the heating mode; performing a dual PID control process if the indoor temperature is less than or equal to the first indoor temperature threshold; wherein the dual PID control process including: calculating the difference between the indoor temperature and a set indoor target temperature to obtain a indoor temperature difference; performing a PID calculation according to the indoor temperature difference to obtain a first target frequency; obtaining a coil temperature of an indoor unit heat exchanger; calculating the temperature difference between the coil temperature and a coil target temperature to obtain a coil temperature difference; performing a PID calculation according to the coil temperature difference to obtain a second target frequency; comparing the first target frequency obtained in the indoor temperature PID calculation with the second target frequency obtained in the coil temperature PID calculation; and performing a frequency control on the compressor in which the greater one between the first target frequency and the second target frequency is used as the target frequency; wherein the coil target temperature is determined according to the indoor temperature, wherein the coil target temperature is negatively correlated with the indoor temperature. calculating the difference between the indoor temperature and a set indoor target temperature to obtain a indoor temperature difference; performing a PID calculation according to the indoor temperature difference to obtain a first target frequency; obtaining a coil temperature of an indoor unit heat exchanger; calculating the temperature difference between the coil temperature and a coil target temperature to obtain a coil temperature difference; performing a PID calculation according to the coil temperature difference to obtain a second target frequency; comparing the first target frequency obtained in the indoor temperature PID calculation with the second target frequency obtained in the coil temperature PID calculation; and performing a frequency control on the compressor in which the greater one between the first target frequency and the second target frequency is used as the target frequency; wherein the coil target temperature is determined according to the indoor temperature, wherein the coil target temperature is negatively correlated with the indoor temperature.