PURPOSE: To make it possible to cope with a complicated shape workpiece in a workpiece gripping device for welding, by rotating any one of drive shafts with the use of a drive device to swing arms, integrally with each other by means of flexible joints.

CONSTITUTION: When a motor 16 rotates counterclockwise both drive shafts coupled with each other by a flexible joint 13, actuators 5 on gripping units 2 are moved upward by means of swing arms 22, connecting rods 43 and inner cables, and therefore, the actuators 5 are opened. In this condition, a body (a) and a panel (b) to be welded together are set on a stationary member while the motor 16 reverses the drive shafts 10 so that the actuators 5 on the gripping units 2 are closed to grip the workpieces in the reversed order. Thus, no obstruction is present around the workpiece attaching position so that the working ability of welding is enhanced, and further, only one drive source is sufficient. Thereby, it is possible to cope with a complicated shape workpiece with the use of such an arrangement that the drive shafts are coupled together by means of the flexible joints.