To provide a substrate processing apparatus which can reduce processing cost.

A processing liquid stored in a recovery tank 110 passes through an impurity removal filter 114 and an ion removal filter 115 via piping 111 by the suction operation of a pump 113, and then it is collected in a refining tank 112. The impurity removal filter 114 removes impurities (water content, etching residue or particle or the like) included in the processing liquid. The ion removal filter 115 removes ions (mainly cathode ion) included in the processing liquid containing an acid liquid, HFEs and a hydrophilic organic solvent. For example, when hydrofluoric acid (HF) is used as an acid liquid, fluorine ion (F-) is removed by the ion removal filter 115. In addition, water content, a hydrophilic organic solvent, or metallic ions or the like can be also removed by the ion removal filter 115.