The stabilizer for shoeing a horse is trailer-style apparatus for securely holding horses for close work such as shoeing operations or veterinary procedures. The unit consists of an open-back rectangular perimeter frame with a trailer hitch assembly and an outboard-mounted wheel assembly on each side. The support frame consists of a vertical support in each corner connected by an upper and lower horizontal support on the front, right and left sides and an upper support on the rear side. Mounted in the center of the right and left sides are adjustable retainer bars which slide horizontally inward to restrain the sides of the horse. Elongated spines with retention notches are mounted upon the retainer bars and allow the handler to attach a number of chains for further restraint purposes. An underbelly harness, a back restraint strap, and a neck restraint strap are also connected to the spines and restraint bars. A removable hoof positioner can be attached to either the lower left or right horizontal support, allowing the handler to slide the positioner to the desired location for the task at hand.