A position/posture measurement device, capable of precisely measuring the position/posture of each article, and a robot system including the device and a robot, in which the robot can be correctly operated with respect to the articles. The position/posture measurement device has: a model data storing part which stores three-dimensional shape data representing the shape of a workpiece as model data; a position/posture calculating part which detects each workpiece and calculates the positions/postures of the workpieces by comparing the model data stored by the model data storing part to the scene data transmitted from a three-dimensional sensor; and a combination evaluating part which calculates evaluation values with respect to all combinations of the positions/postures calculated by the position/posture calculating part, and transmits the combination of the positions/postures having the maximum evaluation value as a measurement result to a robot controller.