To provide a developing liquid supply device used for a developing processor and constituted so that the supply quantity can be accurately controlled even when a supply pump whose specification is varied or the various kinds of processing liquid are used.

The developing liquid supply device used for a developing processor is provided with the supply pump 30 supplying the processing liquid to a processing tank 11 from a supply liquid tank 20 by the extending and contracting action thereof and an extending and contracting frequency detection means 110 detecting the extending and contracting frequency of the pump 30. Besides, it is provided with a discharge quantity measurement means 50 measuring the discharge quantity of the processing liquid by one extending and contracting action of the pump 30 and a control means 100 controlling the pump 30 based on the required supply quantity and the measured discharge quantity.