A socket for an electric part having a body; a plurality of contacts arranged in an array on the body and adapted to be contacted with contact pieces on the electric part when the electric part is inserted into the socket the contacts each having a contacting portion adapted to engage in pressure contact with a corresponding contact piece, a spring portion for exerting a contact pressure on the contacting portion, and a hook-shaped retaining portion and an operating member having an acting portion over which the hook-shaped retaining portions are hooked in sliding engagement with the acting portion and movably mounted on the socket body for moving the retaining portions to cause the contacting portions to be shifted away from the contact pieces of the electric part against the resilient force of the spring portions, the acting portion having retaining element damping walls thereon spaced along the acting portion at intervals greater than the thickness of the retaining portions of the contacts and separating and guiding the retaining portions of adjacent contacts during movement of the acting portion.