A mobile robot, comprising: a moving unit configured to move a main body of the mobile robot; a communication unit configured to communicate with another mobile robot that emits a signal; and a controller configured to recognize a position of the another mobile robot using the signal, and to control the moving unit to follow a trajectory corresponding to a movement of the another mobile robot based on the recognized position; wherein the following of the trajectory by the mobile robot is continuously carried out until a length of the trajectory satisfies a predetermined range; wherein the length of the trajectory to be followed by the main body denotes a remaining length of moving path for the mobile robot to move along the trajectory of the another mobile robot from a current position of the mobile robot to a current position of the another mobile robot; wherein the predetermined range is a distance range satisfying a minimum separation distance (Dl) or more as well as satisfying a maximum separation distance or less; and wherein in response to the length of the trajectory to be followed by the main body deviating from the predetermined range, the controller is configured to output a control command for changing a moving speed of the main body or of the another mobile robot; characterized in that the controller is configured to output a control command for stopping the movement of the another mobile robot in response to whether the length of the trajectory to be followed by the main body exceeds the predetermined range and reaches a critical stop distance; and wherein a sensing area is formed in front of the mobile robot by operation of a sensor and an antenna provided at a front side of the mobile robot to sense the another mobile robot, wherein the mobile robot is configured to perform a searching motion such that the another mobile robot is located within the sensing area, wherein the mobile robot is configured to perform rotation, at a current position, for changing the front side to correspond to a moving direction and a moving speed corresponding to the movement path (d) of the another mobile robot; and wherein the controller is configured to control the moving of the main body to perform the searching motion, while maintaining a stationary state at the current position of the main body, for following a plurality of points forming the trajectory corresponding to the movement of the another mobile robot, when the length of trajectory to be followed by the main body decreases below the predetermined range. a moving unit configured to move a main body of the mobile robot; a communication unit configured to communicate with another mobile robot that emits a signal; and a controller configured to recognize a position of the another mobile robot using the signal, and to control the moving unit to follow a trajectory corresponding to a movement of the another mobile robot based on the recognized position; wherein the following of the trajectory by the mobile robot is continuously carried out until a length of the trajectory satisfies a predetermined range; wherein the length of the trajectory to be followed by the main body denotes a remaining length of moving path for the mobile robot to move along the trajectory of the another mobile robot from a current position of the mobile robot to a current position of the another mobile robot; wherein the predetermined range is a distance range satisfying a minimum separation distance (Dl) or more as well as satisfying a maximum separation distance or less; and wherein in response to the length of the trajectory to be followed by the main body deviating from the predetermined range, the controller is configured to output a control command for changing a moving speed of the main body or of the another mobile robot; characterized in that the controller is configured to output a control command for stopping the movement of the another mobile robot in response to whether the length of the trajectory to be followed by the main body exceeds the predetermined range and reaches a critical stop distance; and wherein a sensing area is formed in front of the mobile robot by operation of a sensor and an antenna provided at a front side of the mobile robot to sense the another mobile robot, wherein the mobile robot is configured to perform a searching motion such that the another mobile robot is located within the sensing area, wherein the mobile robot is configured to perform rotation, at a current position, for changing the front side to correspond to a moving direction and a moving speed corresponding to the movement path (d) of the another mobile robot; and wherein the controller is configured to control the moving of the main body to perform the searching motion, while maintaining a stationary state at the current position of the main body, for following a plurality of points forming the trajectory corresponding to the movement of the another mobile robot, when the length of trajectory to be followed by the main body decreases below the predetermined range.