Abstract:The a. malaris of the Japanese monkey (Macaca fuscata fuscata) was investigated comparatively by means of the acryl plastic injection method. The infraorbital artery itself divided into two to four branches, and each of which entered the same named canal. The medialmost of them gave off the a. malaris immediately before the orifice of the canal, sometimes anastomosing with a twig of the inferior muscular branch of the ophthalmic artery. The a. malaris passed superomedially and slightly posteriorly on the orbital surface of the maxilla, giving off the infraorbital nerve, the infraorbital marginal and the periosteal branches, upto a position in front of the origin of the obliquus inferior muscle, where the artery gave off the inferior nasolacrimal canal and the inferior oblique muscular branches and passed within the bone through a small foramen located in the lacrimomaxillary suture as the superior nasolacrimal canal branch. Rarely, the artery gave off a lacrimal sac branch, and anastomosed with the lacrimalsac branch of the medial palpebral artery of the ophthalmic artery. The inferior nasolacrimal canal branch, giving twigs to the maxillary body and sinus, passed downward along the nasolacrimal canal and formed the inferior portion of the nasolacrimal artery. The superior nasolacrimal canal branch passed medialward and formed the superior portion of the above artery.In conclusion, the author confirmed the presence of the a. malaris in the Japanese monkey, although the main stream of this artery terminated in the nasolacrimal canal branches and formed the nasolacrimal artery.