The invention provides a defrosting control system for a direct-cooling refrigerator. The direct-cooling refrigerator is provided with a main refrigerating circulation system; the defrosting control system comprises a defrosting and refrigerating circulation system, a first switch device and a second switch device, wherein the first switch device is connected with a compressor, a condenser and a freezing chamber evaporator, and the condenser and the freezing chamber evaporator can be selectively connected for starting the main refrigerating circulation system or the defrosting and refrigerating circulation system; the second switch device is connected with the compressor, a refrigerating and freezing evaporation pipe and a defrosting and freezing evaporation pipe, and the refrigerating and freezing evaporation pipe and the defrosting and freezing evaporation pipe can be selectively connected for starting the main refrigerating circulation system or the defrosting and refrigerating circulation system. The defrosting control system provided by the invention can be respectively used for controlling the first switch device and the second switch device, thus the switching between the main refrigerating circulation system and the defrosting and refrigerating circulation system can be realized, and the automatic defrosting of a freezing chamber can be realized.