<p>A game machine enabling lightening of the load of the management of a traveling surface by using the guide line detecting function of a self-traveling body. A game machine comprises a game machine body (10) having a traveling surface (18) on which a guide line (34) is provided and a self-traveling body (30) capable of self-traveling on the traveling surface (18) and having a guide line detecting unit for detecting the guide line (34) and a traveling control unit (110) for controlling the travel of the self-traveling body according to the result of detection by the guide line detecting unit. The guide line detecting unit is a line sensor (50) having light-receiving elements arranged in the lateral direction of the self-traveling body (30) to detect the luminance distribution in a predetermined detection area including the guide line (34) of the traveling surface (18). The self-traveling body (30) is provided with the line width inspecting section (136) for judging the line width of the detected guide line (34) according to the output of the line sensor (50).</p>
