A robot system comprising: a conveying device that conveys workpieces; a plurality of robots (2a, 2b, 2c, 2d) that performs a working operation on the workpieces conveyed by the conveying device; an image capturing device (3a, 3b, 3c, 3d) that is placed at an upper stream side of the conveying device than the plurality of robots (2a, 2b, 2c, 2d) to capture a conveying path of the conveying device; a workpiece detecting device (511, 515, 531) that detects the workpieces on the conveying path on the basis of an image captured by the image capturing device (3a, 3b, 3c, 3d); and a control device (5, 5a, 5b, 5c, 5d) that controls operations of the plurality of robots, and the control device (5, 5a, 5b, 5c, 5d) including: an operation instruction unit (513, 517, 532) that generates an operation instruction for performing a holding operation on the workpieces on the basis of a detection result of the workpiece detecting device and transmits the operation instruction to the robots; and an allocating unit (512, 519, 534) that determines which of the plurality of robots to which the operation instruction unit transmits the operation instruction on the basis of conveying situations of the workpieces obtained from the detection result of the workpiece detecting device (511, 515, 531), characterized in that the control device (5a, 5b, 5c, 5d) instructs, for each of divided areas obtained by dividing an image area of the image, the robot (2a, 2b, 2c, 2d) corresponding to the divided area to perform the holding operation on the workpieces belonging to the divided area, and the control device (5a, 5b, 5c, 5d) calculates an inclination of the workpieces on the conveying path and changes sizes of the divided areas in accordance with the calculated inclination. a conveying device that conveys workpieces; a plurality of robots (2a, 2b, 2c, 2d) that performs a working operation on the workpieces conveyed by the conveying device; an image capturing device (3a, 3b, 3c, 3d) that is placed at an upper stream side of the conveying device than the plurality of robots (2a, 2b, 2c, 2d) to capture a conveying path of the conveying device; a workpiece detecting device (511, 515, 531) that detects the workpieces on the conveying path on the basis of an image captured by the image capturing device (3a, 3b, 3c, 3d); and a control device (5, 5a, 5b, 5c, 5d) that controls operations of the plurality of robots, and the control device (5, 5a, 5b, 5c, 5d) including: an operation instruction unit (513, 517, 532) that generates an operation instruction for performing a holding operation on the workpieces on the basis of a detection result of the workpiece detecting device and transmits the operation instruction to the robots; and an allocating unit (512, 519, 534) that determines which of the plurality of robots to which the operation instruction unit transmits the operation instruction on the basis of conveying situations of the workpieces obtained from the detection result of the workpiece detecting device (511, 515, 531), characterized in that the control device (5a, 5b, 5c, 5d) instructs, for each of divided areas obtained by dividing an image area of the image, the robot (2a, 2b, 2c, 2d) corresponding to the divided area to perform the holding operation on the workpieces belonging to the divided area, and the control device (5a, 5b, 5c, 5d) calculates an inclination of the workpieces on the conveying path and changes sizes of the divided areas in accordance with the calculated inclination. an operation instruction unit (513, 517, 532) that generates an operation instruction for performing a holding operation on the workpieces on the basis of a detection result of the workpiece detecting device and transmits the operation instruction to the robots; and an allocating unit (512, 519, 534) that determines which of the plurality of robots to which the operation instruction unit transmits the operation instruction on the basis of conveying situations of the workpieces obtained from the detection result of the workpiece detecting device (511, 515, 531), characterized in that the control device (5a, 5b, 5c, 5d) instructs, for each of divided areas obtained by dividing an image area of the image, the robot (2a, 2b, 2c, 2d) corresponding to the divided area to perform the holding operation on the workpieces belonging to the divided area, and the control device (5a, 5b, 5c, 5d) calculates an inclination of the workpieces on the conveying path and changes sizes of the divided areas in accordance with the calculated inclination.