A connector includes an outer housing including an engagement catch, an inner housing and a sliding member. The inner housing includes an engagement latch, and a pair of locking arms each provided with the engagement latch. The inner housing includes a slide channel having the pair of locking arms disposed at both sides. The sliding member includes a pair of latching arms each provided with a latch. When the first housing and the second housing are engaged with each other, the first housing and the second housing allow the sliding member to pass through the slide channel, and when the sliding member slides the slide channel, the pair of latching arms are deflected so as to decrease a gap therebetween by depressions from the respective locking arms.