Abstract: A folding bicycle includes an X-shaped frame consisting of a lower front, a lower rear, an upper front, and an upper rear supporting arm; a front and a rear wheel respectively mounted to distal ends of the lower front and lower rear supporting arms; a saddle pivotally connected to a distal end of the upper rear supporting arm; a handlebar rotatably connected to a distal end of the upper front supporting arm; a locking mechanism mounted between the lower front and lower rear supporting arms for holding the frame in an extended position; and a steering mechanism arranged between the handlebar and the front wheel for steering the bicycle.