BACKGROUND Rathke cleft cysts (RCCs) arise from the remnant of Rathke pouch and are usually found in the intermediate lobe. In most cases, RCCs remain intrasellar and extend into the suprasellar region. Rarely, they emerge entirely into the suprasellar cistern-entirely suprasellar Rathke cleft cyst (ESSRCC). METHODS We retrospectively reviewed medical records of 7 patients (5.5%) with ESSRCC among 128 patients with a diagnosis of RCC from January 1994 to September 2018. Of RCC cases, 70 were treated surgically. Patient age and sex, symptoms, magnetic resonance imaging findings, cyst diameter, presence of preoperative or postoperative hypopituitarism, operative procedures and complications, and functional outcomes at the final follow-up were investigated. RESULTS All patients with ESSRCC were women with mean age 45.7 years (range, 29-69 years) at diagnosis. All patients experienced headache, mainly in the retro-orbital region. Mean ESSRCC diameter was 9.9 mm (range, 6-14 mm). Most cases exhibited hyperintensity on both T1-weighted and T2-weighted imaging. The endoscopic endonasal transtuberculum sellae approach relieved headache effectively and safely in 5 patients. Postoperative endocrinologic functions were almost entirely preserved. No patient experienced recurrence during the follow-up period. CONCLUSIONS RCCs should be considered in the differential diagnosis of suprasellar cysts. The endoscopic endonasal transtuberculum sellae approach has an advantage in visualizing these lesions owing to the direction of light from the endoscope. Headache could be treated effectively with the endoscopic endonasal transtuberculum sellae approach without recurrence of cysts or pituitary dysfunction.