To provide a robot device capable of accurately detecting a workpiece and carrying it in spite of its simple structure.

A robot device 20 adapted to carry a workpiece 21 into or out of a plurality of delivery parts comprises: a device body holding therein a drive source; a driving shaft driven by the drive source; an arm body 29 involving a base arm 30a connected at its one end to the driving shaft and a tip arm 30c connected at its one end turnably to the other end of the base arm 30a and formed at the other end with a holder part 32 for holding the workpiece 21, which telescopically moves by the rotation of the driving shaft; and a sensor for detecting the workpiece 21 held in the holder part 32 with the arm body 29 integrated with the base arm 30a being shortened in length.