A robot controller which is constructed so that a control part for controlling a robot and a portable teaching operating part communicate with each other by wireless communications, said portable teaching operating part comprising: emergency stop operating means for cutting off the supply of electric power to the driving motors of said robot to place said robot in an emergency-stop state; emergency stop release operating means for releasing said emergency-stop state to restore said robot to a state in which its movement is possible; a plurality of communications data generating circuits, the plurality for generating communications data relating to emergency stopping based on operations of said emergency stop operating means, and for generating general data expressing information inputted by a keyboard provided in said teaching operating part and unrelated to the data relating to emergency stopping; and transmitting means for transmitting communications data relating to emergency stopping and general data, generated in said plurality of communications data generating circuits, received through transmission data switching means, to said control part by wireless communications, said control part comprising: receiving means which receive, from said transmitting means, general data and communications data relating to emergency stopping generated by the respective communications data generating circuits, wherein: each of said plurality of communications data generating circuits is arranged to generate communications data expressing an emergency stop command after receiving an emergency stop signal, indicating an emergency stop state, from the emergency stop operating means and to generate communications data expressing an emergency stop release command after receiving a signal, indicating release of the emergency stop state, from the emergency stop release operating means, wherein at least one of the plurality of communications data generating circuits receives the emergency stop signal via a respective CPU provided in said teaching operating part; and a first one of said at least one of said plurality of communications data generating circuits generates both general data expressing information inputted by a keyboard provided in said teaching operating part, and also communications data expressing an emergency stop command, and wherein said receiving means is arranged to place said robot in an emergency-stop state upon receiving communications data expressing an emergency stop command generated by any one of said plurality of communications data generating circuits. emergency stop operating means for cutting off the supply of electric power to the driving motors of said robot to place said robot in an emergency-stop state; emergency stop release operating means for releasing said emergency-stop state to restore said robot to a state in which its movement is possible; a plurality of communications data generating circuits, the plurality for generating communications data relating to emergency stopping based on operations of said emergency stop operating means, and for generating general data expressing information inputted by a keyboard provided in said teaching operating part and unrelated to the data relating to emergency stopping; and transmitting means for transmitting communications data relating to emergency stopping and general data, generated in said plurality of communications data generating circuits, received through transmission data switching means, to said control part by wireless communications, each of said plurality of communications data generating circuits is arranged to generate communications data expressing an emergency stop command after receiving an emergency stop signal, indicating an emergency stop state, from the emergency stop operating means and to generate communications data expressing an emergency stop release command after receiving a signal, indicating release of the emergency stop state, from the emergency stop release operating means, wherein at least one of the plurality of communications data generating circuits receives the emergency stop signal via a respective CPU provided in said teaching operating part; and a first one of said at least one of said plurality of communications data generating circuits generates both general data expressing information inputted by a keyboard provided in said teaching operating part, and also communications data expressing an emergency stop command, and wherein said receiving means is arranged to place said robot in an emergency-stop state upon receiving communications data expressing an emergency stop command generated by any one of said plurality of communications data generating circuits.