Mucinous adenocarcinoma (MAC) is commonly found in the gastrointestinal tract but head and neck localisations are very rare. This article presents the case of a 67-year-old patient suffering from a minor salivary gland MAC of the left buccal mucosa, who was treated in the Department of Cranio-Maxillofacial Surgery in Krakow due to multiple recurrences of the tumour. The results of immunohistochemical staining, the course of surgical treatment and follow-up, as well as a review of literature are also discussed.