A displacement detection type force sensor, having a mechanism for relaxing deformation of a member due to a factor other than an external force. The force sensor has at least one of: a first relaxation part elastically deformable along a plane perpendicular to a first axis, and provided to at least one of a first substrate part, a first connection part, a second substrate part and a second connection part; and a second relaxation part elastically deformable along the first axis, and provided to at least one of the second substrate part, the second connection part, a third substrate part and a third connection part.