Supernumerary nostril is a very rare congenital anomaly. It can be unilateral or bilateral, and it sometimes occurs in the presence of other congenital deformities. Behind the external opening of a supernumerary nostril is a small accessory nasal cavity, which may or may not communicate with the normal nasal cavity on the same side. We describe a new case in which the supernumerary nostril with a small accessory nasal cavity, which did not communicate with the normal nasal cavity on the same side, appeared in a young girl who also had microcornea and congenital cataract. The accessory nasal cavity was successfully removed surgically. We believe that this case may represent the first reported case of a supernumerary nostril with a congenital cataract on the same side. We also discuss the hypotheses that have been proposed to explain supernumerary nostrils.