Herein, we report an exceptional case of a young female patient with progressive enlargement of a sellar mass, clinically suggestive of pituitary adenoma. Histopathology, however, demonstrated Rathke's cleft cyst associated with salivary gland remnants. In contrast to the majority of prior reports, the ectopic salivary glands were found in close proximity to the anterior pituitary lobe and showed active production of mucous secret, which caused progressive growth and symptoms in this patient. We further demonstrate nerve fibers surrounding the ectopic salivary glands, thereby suggesting parasympathetic innervation as a plausible mechanism triggering seromucous secretion. Neurosurgeons and neuropathologists need to be aware of this rare clinical condition expanding the spectrum of differential diagnoses of sellar masses.