A refrigerator and a driving method thereof are disclosed. The number of vibration of each compressor, evaporation temperature of each evaporator, or an open time of a refrigerant switching valve is detected to determine whether the flow of refrigerant is biased so as to adjust a cooling capability of the compressor or an open value or open time of a refrigerant switching valve, thereby uniformly distributing the refrigerant into first and second evaporators. Accordingly, the refrigerator can be driven with an independent refrigeration cycle corresponding to a load of a freezing chamber or a refrigerating chamber, resulting in reduction of unnecessary power consumption of the refrigerator.