"Congenital macrostomiais rporrted as lateral facial cleft or a transverse facial cleft, has received little attention in the literature. Congenital macrostomia is characterized by a spectrum from a simle widengin of the oral commissure to a full thickness defect of the cheek.
 McCarthy described the classic commissuroplasty as follows. (1) To account for anticipated wound contraction, the new oral commissure wans moved 2 to 3mm laterally.(2) the diviided orbicularis oris muscle should be secured after transposin each other. (3) A z-plasty custneous closure should be done. 
 We have repaired 6 cases of congenital macrostomia with the classic commissuroplasty proposed by McCarthy and found that the reconstructed oral commissure was tend to be displaced laterally and inferioly. 
 So, we devised a modifed commissuroplasty to prevetnthis problem as follows.
(1) The new commissure is positioned at the same as the opposite side. (2) The skeletosixed muscle bundles are freed from zygomaticus, risorius and depressor anguli oris muscle and the bundles should be fixed at the figher position after transposition. (3) the commissure is reconstructed with vermilion commissure flap from upper lip and cutaneous coverage is done by z plasty.
 Longterm follow up of one case of congenital macrostomiaafter this modified commissruoplasty reveals that the new commissure is not displaced with symmetry
"