A washing machine comprises a first washing drum with a first heater and a second washing drum with a second heater. Before the first washing drum performs a heating procedure, it is necessary to determine whether the second washing drum is performing the heating procedure; if not, the first washing drum performs the heating procedure; if yes, it is necessary to determine whether the remaining heating time of the second washing drum is less than a set value, T min; if yes, the first washing drum pauses the heating procedure; when the second washing drum finishes performing the heating procedure, the first washing drum then performs the heating procedure; if not, remaining heating time of the first washing drum and that of the second washing drum are determined, whichever drum having the shorter remaining heating time performs the heating procedure first, while the other drum performs the heating procedure second.