A method for cleaning a semiconductor wafer by using a chemical tank containing an SC-2 solution including, a plurality of the chemical tanks are used, and among SC-2 solutions contained in the plurality of chemical tanks, an HCl concentration in an SC-2 solution contained in a chemical tank to be finally used is lowered to the lowest to clean the semiconductor wafer. The method for cleaning a semiconductor wafer thus provided can improve the particle level in SC-2 cleaning for a semiconductor wafer without degrading the metal impurity level on the semiconductor wafer surface.