OBJECTIVE:: To describe canaliculosinostomy performed to resolve epiphora caused by nasolacrimal duct obstruction and to report the outcome of horses undergoing this procedure. STUDY DESIGN:: Case series. ANIMALS:: Seven horses with uni- or bilateral nasolacrimal duct obstruction. METHODS:: The ventral lacrimal punctum and canaliculus were expanded with catheters of increasing diameter until a 14 gauge, Jamshedi needle could be passed into and through the lacrimal sac into the caudal maxillary sinus. One end of a plastic tube was inserted through the needle into the sinus, and the needle was withdrawn over the tubing. Using a hubless needle, the other end of the tube was passed through the lower eyelid leaving a segment of tubing exposed ventral to the eyelid. The end of the tubing within the sinus was exteriorized through a trephine hole in the frontal sinus and then tunneled beneath the skin adjacent to the osteotomy using a hubless needle, leaving a segment of tubing exposed on the forehead. Exposed tubing was sutured to the skin. The tubing was removed at 5–6 weeks. RESULTS:: Canaliculosinostomy was easily performed with the horses sedated. Five horses had resolution of epiphora, and 2 had improvement. CONCLUSION:: Canaliculosinostomy to divert lacrimal secretions into the sinuses resolves or improves epiphora caused by nasolacrimal duct obstruction and provides a good functional and cosmetic outcome. Canaliculosinostomy can be performed in the sedated horse.