The invention provides a protective riding boot bootleg forming method which comprises the steps of material preparation, rear main heel forming, steel head armoring, support bottom nailing, protective back adhesion, upper arrangement, white emulsion application for lasting, white emulsion application for the support bottom, head surface folding warping, primary head upper clamping, head inner lasting pull, steel head sleeving, removal of support bottom head position fixing nails, steel head protection pad middle sole adhesion, secondary head upper clamping, middle upper pull, rear upper sweeping, heelpiece flatting, shoe hammering and the like. Riding boots formed by adopting the method are comfortable to wear, make a user to flexible to move and have a good instep protecting function.