A working machine control device that is adapted to remotely control a working machine including a lower travelling body and an upper slewing body that slews with respect to the lower travelling body, the working machine control device comprising: a display unit that is provided outside the working machine; a camera that is adapted to be disposed on the upper slewing body and to obtain a captured image by imaging a particular part that is a part of the lower travelling body; and a controller that is provided outside the working machine, wherein the controller includes: a setting unit that sets a target slewing angle of the upper slewing body with respect to the lower travelling body; and a display control unit that causes the display unit to display a display screen in which a target image indicating a target position of the particular part is displayed in a superimposed manner at a position on the captured image, the position being where the particular part is displayed when a slewing angle (θ) of the upper slewing body with respect to the lower travelling body reaches the target slewing angle, characterized in that the controller is adapted such that as a display position of the particular part corresponding to the target slewing angle, a position on the captured image calculated in advance in consideration of the position of the camera in the upper slewing body, the size of the upper slewing body, and the size of the lower travelling body is employed. a display unit that is provided outside the working machine; a camera that is adapted to be disposed on the upper slewing body and to obtain a captured image by imaging a particular part that is a part of the lower travelling body; and a controller that is provided outside the working machine, wherein the controller includes: a setting unit that sets a target slewing angle of the upper slewing body with respect to the lower travelling body; and a display control unit that causes the display unit to display a display screen in which a target image indicating a target position of the particular part is displayed in a superimposed manner at a position on the captured image, the position being where the particular part is displayed when a slewing angle (θ) of the upper slewing body with respect to the lower travelling body reaches the target slewing angle, characterized in that the controller is adapted such that as a display position of the particular part corresponding to the target slewing angle, a position on the captured image calculated in advance in consideration of the position of the camera in the upper slewing body, the size of the upper slewing body, and the size of the lower travelling body is employed. a setting unit that sets a target slewing angle of the upper slewing body with respect to the lower travelling body; and a display control unit that causes the display unit to display a display screen in which a target image indicating a target position of the particular part is displayed in a superimposed manner at a position on the captured image, the position being where the particular part is displayed when a slewing angle (θ) of the upper slewing body with respect to the lower travelling body reaches the target slewing angle, characterized in that the controller is adapted such that as a display position of the particular part corresponding to the target slewing angle, a position on the captured image calculated in advance in consideration of the position of the camera in the upper slewing body, the size of the upper slewing body, and the size of the lower travelling body is employed.