A processing liquid supplying apparatus performs an ejecting step in which a processing liquid suctioned into a pump passes through a filter device and is ejected from an ejecting part without returning the processing liquid back to the pump; a returning step in which the processing liquid suctioned into the pump is returned to a processing liquid source side of a mixing section; and a replenishing step in which the processing liquid returned to the processing liquid source side is suctioned into the pump together with the processing liquid replenished from the processing liquid source. The processing liquid passes through the filter device in at least one of the returning step and the replenishing step. The amount of the processing liquid returned to the processing liquid source side in the returning step is larger than the amount of the processing liquid ejected from the ejecting part in the ejecting step.