Disclosed herein is a damper for washing machines. The damper comprises a cylinder and a piston interactively coupled to each other in a state wherein the cylinder is connected to a tub and the piston is connected to a base, a first friction member provided around the piston for generating a frictional force when the piston moves inside the cylinder, a slider coupled to the piston inside the cylinder so as to move together with the piston if the piston moves beyond a predetermined displacement range, and a second friction member provided around the slider for generating a frictional force when the slider moves inside the cylinder. The damper configured as stated above generates different damping forces according to the vibration degrees of the tub, thereby effectively attenuating the vibration of the tub.