BACKGROUND Sublingual salivary gland tumours are very rare but are mostly malignant. As very limited literature is available, we present a rare case of mucoepidermoid carcinoma (MEC) of sublingual salivary gland. METHODS A56-year-old female presented with an asymptomatic swelling of 15-year duration in the floor of the mouth and chin region. METHODS Mandibular occlusal view, computed tomography scan, and ultrasonogram revealed calcification and the tumour to be of salivary origin. Incisional biopsy showed clear cell changes. METHODS The sublingual and submandibular salivary gland along with the associated nodes was excised through transoral approach with midline osteotomy. RESULTS The histopathologic diagnosis of excised specimen was "Intermediate grade MEC" with clear cell changes, stromal hyalinization, and local invasion. The patient was followed up for 12 months, and there was no evidence of any recurrence. Sublingual salivary gland malignancies show early invasion and a higher rate of metastases, thus requiring a vigilant intervention.