Conjunctival mucoepidermoid carcinoma is a very rare but highly aggressive conjunctival neoplasm with 42 previously reported cases. We report the case of a 56-year-old male with a left ocular surface squamous neoplasm, which was subsequently treated with excision and autoconjunctival graft. Histopathology of the operative specimen reported a low-grade conjunctival mucoepidermoid carcinoma, and the patient was then treated with an adjunctive course of mitomycin C. On review 10 months after lesion excision, there was no recurrence, and the patient was otherwise well. Due to its rare incidence, difficult clinical diagnosis, and accompanying poor prognosis, conjunctival mucoepidermoid carcinoma should always be considered in the differential diagnosis of conjunctival neoplasms, and full histopathologic examination, including mucin-staining techniques, of all suspicious conjunctival biopsies should occur.