To prevent a returning failure of a contact piece by suppressing unnecessary deformation of the contact piece in a high load test or an actual use.

A movable contact for switch 1 comprises: a contact piece 2 formed by bending a conductive spring plate in a dome-like shape so that it can be reversely returned; an expanded portion 5 protruding to a convex side of the dome-like shape for increasing stiffness formed at the center of a convex 3 of the contact piece 2; a plurality of contacts 6 formed on a concave 4 of the contact piece 2 on a concentric circle around the expanded portion 5 by a small projection protruding to a concave side of the dome-like shape; and a recess 7 for preventing deformation formed on the convex side face of the expanded portion 5 by denting a peripheral portion of the expanded portion 5 in a direction to the center thereof on a straight line connecting the center of the expanded portion 5 and each of the contacts 6.