A connector includes a first housing accommodating first terminals, a second housing accommodating second terminals connectable to the first terminals and fittable to the first housing, short-circuit terminals accommodated in the first housing and each having a pair of contact pieces that respectively come in contact with corresponding first terminals adjacent to each other, releasing parts provided in the second housing and configured so as to displace the contact pieces, thereby releasing contacts between the first terminals and the contact pieces, tin plating films formed on respective contact surfaces of the first terminals and the contact pieces coming into contact with each other, and sliding parts provided in the second housing and positioned ahead of the releasing parts in a fitting direction between the first housing and the second housing to displace the contact pieces thereby allowing the contact pieces to slide on the first terminals.