Abstract: An oval-tracked exercise device includes a base assembly, a supporting frame assembly fastened on the base assembly, a treadle crank assembly fastened on the rear end of the supporting frame assembly and a wheel assembly fastened at the bottom end of the supporting frame assembly. The bottoms of the treadles have bottom shafts which are fixed to the bottom ends of the front standing shafts. In treading, the transmission gear assembly will be driven by the bottom shaft of the treadle crank assembly to rotate the wheel assembly, so that the front standing shafts and the handles are able to make a pivoting movement on the front lateral shaft in order for the user to exercise the whole body. When the handles are inserted into connecting tubes at the front end of the front lateral shaft, the handles are unable to swing with the front standing shaft and the user is able to exercise only the buttocks without moving the upper body.