Asymmetrical alar flare without a history of trauma, surgery, or congenital clefting is extremely rare; therefore, a thorough investigation into the underlying reasons for the asymmetry should be undertaken before a unilateral alar base resection is performed. Nasoalveolar cyst is a readily apparent diagnosis that should not be missed after proper intranasal and intraoral examination. Excision is recommended via a sublabial approach. We describe a patient in whom a unilateral alar base reduction was initially recommended, when in fact she had a nasoalveolar cyst. We also discuss the histologic characteristics, embryological pattern, and differential diagnosis.