The invention relates to an air-cooled variable-frequency multi-door refrigerator capable of working with low noise work at night and a control method thereof. The refrigerator comprises a photosensitive input unit, a refrigerator door switch, an MCU (Multipoint Control Unit), a variable-frequency compressor driving unit, a variable-frequency compressor, a variable-speed fan driving unit, a variable-speed fan, a VALVE electromagnetic valve driving unit and a VALVE electromagnetic valve, wherein the MCU is provided with an analog-digital conversion part, a comparison part, a judgment part, a switching part and a timing part. A photosensitive sensor arranged on a display board can be used for sensing the environmental brightness of the refrigerator; differentiated intelligent control is carried out comprehensively through processing by MCU so as to determine a current environment is day or night; when the current environment is night, the variable-frequency compressor is operated at low speed; and when the current environment is day, the variable-frequency compressor is operated at high speed. On the premise of ensuring the performance of the refrigerator, the noise of the refrigerator is reduced to the maximum by the differentiated intelligent control so that a customer feels comfortable when using the refrigerator.