A substrate processing apparatus 10 includes a holding table 20 for rotatably holding a wafer W, a nozzle 40 for supplying chemical solutions L1 and L2 to the wafer W, at least one light irradiation units G1 and G2, and a pot 30 placed in the outer radius of the holding table 20for collecting the processing solutions L1 and L2 that are scattered from the wafer W. The pot 30 also includes a cover 70 that can be moved in the direction of the axis of the holding table 20so that a plurality of chemical solution collecting chambers M1 and M2 are formed in the pot by changing the position of the cover 70.