A handsaw for holding a saw blade for cutting is disclosed to include a handle having an cantilever bar, an extension bar pivoted to the cantilever bar and turnable relative to the handle between a received position and an extended position, a blade-retaining arm pivoted to one end of the extension bar remote from the handle and turnable about the axis of the extension bar, and two blade retaining members respectively provided at the handle and the blade-retaining arm for the mounting of a saw blade when the extension bar is turned to the extended position.