A photoresist stripping solution comprising (a) a specified quaternary ammonium hydroxide, such as tetrabutylammonium hydroxide, tetrapropylammonium hydroxide, methyltributylammonium hydroxide or methyltripropylammonium hydroxide, (b) a water-soluble amine, (c) water, (d) a corrosion inhibitor and (e) a water-soluble organic solvent, the compounding ratio of component (a) to component (b) being in the range of from 1:3 to 1:10 by mass, as well as a method of stripping photoresists using the solution. The stripping solution of the invention assures effective protection of Al, Cu and other wiring metal conductors against corroding as well as efficient stripping of the photoresist film, post-ashing residues such as modified photoresist film and metal depositions. It also assures efficient stripping of Si-based residues and effective protection of the substrate (particularly the reverse side of a Si substrate) from corroding.