An angular velocity sensor comprises a mass body part including a first mass body and a second mass body, an internal frame supporting the first mass body and the second mass body, one or more first flexible parts connecting the first mass body or the second mass body to the internal frame, one or more second flexible parts connecting the first mass body or the second mass body to the internal frame, an external frame supporting the internal frame, at least one third flexible part connecting the internal frame to the external frame, and at least one fourth flexible part connecting the internal frame to the external frame. At least one of the second flexible parts is connected to the first mass body in line with the center of gravity of the first mass body. At least one other of the second flexible parts is connected to an eccentric portion of the second mass body.