Intramuscular myxoma (IM) is a benign intramuscular neoplasm composed of fibroblasts and abundant myxoid stroma. IMs most commonly affect larger skeletal muscles, while those affecting the oral and maxillofacial regions are rare, with a small number of documented cases in the available literature. The aim of the present study was to describe a highly rare case of an IM within the hyoglossus muscle of the tongue in a 74-year-old male. The patient presented with a painless mass in the submental space that had been growing slowly for more than five years. A computed tomography scan revealed a hypodense lesion located in the root of the tongue. The mass was easily excised with thin margins, including only a small amount of the adjacent muscle tissue. The pathological diagnosis of the mass was an IM. The patient made an excellent recovery following the surgery and the follow-up three years later revealed no local recurrence. IMs of the hyoglossus muscle are highly rare, however must be considered in the differential diagnosis of swellings in the root of the tongue region.