Abstract: A cleaning method and a cleaning tool for a negative-pressure component for battery formation are provided. The cleaning tool includes a liquid storage tank for storing a cleaning liquid, a power member connected with the liquid storage tank, a storage cup, and a liquid guide member. The storage cup is communicated with the negative-pressure component through the guide member. The cleaning tool has a first pipeline defining a flow from the liquid storage tank to the storage cup. The power member provides power for the flow of the cleaning liquid in the first pipeline to inject the cleaning liquid in the liquid storage tank into the storage cup. The cleaning liquid is sucked into the negative-pressure component from the storage cup by an existing negative-pressure power source of the negative-pressure component. Air sucked by the negative-pressure power source is mixed with the cleaning liquid in the negative-pressure component.