Disclosed herein is a robot, which has a simple structure and makes a gesture in a curved shape. The robot includes a body part, at least one cam member symmetrically arranged at both sides of the inside of the body part, an outer cover member surrounding the at least one cam member, and a linear moving device to linearly move the at least one cam member. The shape of the outer cover member is varied, under the condition that the outer cover member is adhered closely to the at least one cam member, according to the movement of the at least one cam member.