The invention relates to a control system and control method for a frostless refrigerator heater. The control system for the frostless refrigerator heater comprises a singlechip processor, as well as a refrigerating chamber temperature sensor, a freezing chamber temperature sensor, a defrosting temperature sensor and a door switching signal which are respectively connected with the singlechip processor, wherein the singlechip processor is respectively connected with a compressor, a fan motor, a defrosting heater and an electric air door through driving circuits; the control system also comprises a temperature control circuit which is connected between the driving circuits of the defrosting temperature sensor and the defrosting heater. According to the invention, by additional arrangement of the temperature control circuit, the function of controlling the defrosting heater by hardware circuits can be achieved, namely, no matter what status the single chip processor is in, the defrosting heater can be forced to power off when the temperature of the defrosting temperature sensor RV is too high, thus the safety performance of the product can be improved and the requirement of the safety standard can be satisfied.