A hinge damper is configured to be adhered to a door hinge of the furniture having a door to attenuate impact and is designed in a small size but to attenuate a large amount of impact. In the hinge damper, first and second seals are formed in an oil seal to prevent air from being introduced. A cross rib is formed on a piston to absorb a larger amount of impact with a small size. The hinge damper can be sized as small as a size of a screw used for fixing the hinge.