Provided is a control technique for achieving formation control which is applicable even when there is a non-connection location in a common portion between a set of initial positions of robot units and a set of target positions of the robot units. Each of a plurality of robots constituting a mobile robot includes a position distance calculation command transmission unit 1, a position distance calculation command transfer unit 2, a return position distance calculation command transmission unit 3, a direction storage unit 4, a return position distance calculation command transfer unit 5, a first head robot determination command transmission unit 6, a void generation order determination unit 7, a void generation command transfer unit 8, a push command transmission unit 9, a return push command transmission unit 10, a return push command transfer unit 11, a void operation command transmission unit 12, a first movement unit 13, a void operation command transfer unit 14, a movement command transmission unit 15, a return movement command transmission unit 16, a second movement unit 17, a pull command transmission unit 18, a return pull command transmission unit 19, a third movement unit 20, a control unit 21, a set updating unit 22, and a second head robot determination command transmission unit 23.