A mass measurement device measures the mass of an article, even when the article is being moved. A mass measurement device includes a robot hand, a robot arm, a force sensor, an acceleration sensor, and a control unit. The robot hand holds an article (Q). The robot arm moves the robot hand. The force sensor is provided between the robot hand and the robot arm and measures force acting on the article (Q) during movement. The acceleration sensor measures acceleration acting on the article (Q) during the movement. The control unit runs and controls the robot hand and the robot arm, and calculates the mass of the article (Q) on the basis of the force and acceleration acting on the article (Q) during the movement.