My invention is an ankle reinforcing device for the prevention of medial and/or lateral ankle injuries such as sprains or breaks. The object of the invention is to provide an inexpensive but highly effective device which will allow free and unhampered movement of the wearers foot while engaged in athletic events or other physical activity but will prevent movement in such a direction and to such an extent that would result in spraining or breaking an ankle. The ankle reinforcing device is constructed from an underlying member which covers all or part of the foot and part of the leg above the ankle, reinforcing members attached to or integral with the underlying member, and means to securely attach the device to the wearer. The reinforcing members are arranged in a pattern to prevent excessive movement of the ankle in the medial and/or lateral directions, while allowing free up and down movement of the foot.