A washing machine comprises a hinge device including a cam member, a lever, and an elastic member, and the cam member comprises an outer circumference surface including a first section, a second section and a third section disposed between the first section and the second section having a curvature different from each other. The cam member is profiled to be disposed at a first position in which the door is automatically opened, a second position in which the door is automatically closed, and at a third position in which an external resultant force becomes 0 (zero), when the lever is in contact with each section. Therefore, it is possible to control a closing speed of the door and simplify the power transmission method by using the cam, reduce the material cost by reducing the number of parts, and secure the reliability of driving of the washing machine.