The invention discloses a monitoring device for a substation. The monitoring device comprises a guide rail and a camera body, wherein a main rail groove of which the cross section is in the shape likean inverted Chinese character 'tu' is formed in the guide rail; a moving device is arranged in the main rail groove; the camera body is connected with the moving device; the moving device comprises abottom plate, a step motor and driving wheels, wherein the step motor is fixed on the bottom plate, and is used for driving the driving wheels to rotate; the driving wheels are gears; and racks matched with the corresponding gears are arranged in the main rail groove in the length direction of the guiding rail. The monitoring device disclosed by the invention has the advantages that the guide rail is additionally arranged in the substation, and the camera body drives the driving wheels to move on the guide rail by the step motor, so that the position of the camera can be adjusted according tothe position of the equipment which needs to be seen clearly, the arranging number of the cameras in the substation is reduced, and the construction cost is reduced; and besides, the step motor cooperates with the gears and the racks, so that the moving position of the camera can be accurately controlled, and the camera is convenient to adjust to be in an appropriate angle to see the specific running state of the equipment which needs observation clearly.