A water replenishment control method for a multi-drum washing machine. The washing machine comprises at least a first washing drum and a second washing drum. While the first washing drum is in a washing process, if the water level of washing water is lower than a set value, then a water replenishment process is executed, and before that, it is necessary to determine whether or not the second washing drum is executing a water replenishment process; if yes, the first washing drum pauses the water replenishment process, and the second washing drum executes precedence preferentially; if no, the first washing drum executes water replenishment process and terminates it when the water level of the washing water reaches a set water level.