To provide a connecting device capable of connecting movable bodies by enabling close contacts between them in a full length almost equivalent to a length obtained by multiplying a full length in an independently traveling state by the number of connected movable bodies at the time of connected traveling of the movable bodies, and connecting and disconnecting the movable bodies without elevating them.

The rear end of each movable body 5 traveling along a traveling rail 2 is provided with a rear dog 15 which is supported at one end swingably only in either upward or downward direction, and has an engagement part 17 at the other end directed horizontally backward. The front end of each movable body is provided with a front dog 20 which is supported at one end swingably in the same direction as the rear dog 15, and has a hook part 22 at the other end directed horizontally forward, which can be engaged with the engagement part 17 when the rear dog 15 is in a horizontal state, and an inclined surface 23 in the opposite side face of the hook part, which contacts with and swings the rear dog 15, and is provided with a means 30 for swinging the front dog. At a point for connecting and disconnecting the movable bodies, a cam member 35 contacting with and driving the swinging means 30 is arranged by the side of the traveling rail 2, thereby constituting the connecting device.