There is provided a connector that allows easy engagement even when visual judgment is not possible and that has superior durability as well. In a connector for connecting a first connecting cable connected to one end of a socket and a second connecting cable connected to one end of a plug, through engagement between the socket and the plug, the socket includes a cutout portion formed by cutting away at least one portion from one opening of a cylinder along the peripheral direction thereof, the cutout portion having a V-shape at its deepest portion, a first guiding portion projecting from at least one portion of the opening along the peripheral direction, the first guiding portion having a substantial V-shape at its leading end, and a retaining portion to be retained to a lateral face of the cylinder at the time of engagement with the plug, thus retaining this engagement. The plug includes a second guiding portion engageable into the cutout portion and having a substantial V-shape at its leading end and a pawl portion to be retained to the retaining portion at the time of the engagement with the socket.