endoscopic endonasal transsphenoidal resection has been accepted as a routine therapy for pituitary adenoma, but the postoperative hospital stay is typically several days long. With the advantages of reduced cost and improved patient satisfaction, the application of ambulatory surgery (AS) has developed rapidly. However, AS was still rarely adopted in neurosurgery. Here we designed an AS treatment protocol for pituitary adenoma with the endoscopic endonasal approach (EEA), and reported our initial experiences regarding the safety and efficacy of the AS protocol. 63 patients who presented with pituitary adenoma were screened at the Department of Neurosurgery, Tangdu Hospital from July to September, 2017. A total of 20 pituitary adenoma patients who met the inclusion criteria underwent EEA surgery using this evidence-based AS protocol, which emphasized adequate assessment for eligibility, full preparation to minimize invasiveness, enhanced recovery, and active perioperative patient education. Of the 20 patients enrolled, 18 were discharged on the afternoon of the operation day with a median total length of stay (LOS) of 31 hours (range, 29-32) hours. The median LOS after surgery was 6.5 (range, 5-8) hours. Two patients were transferred from the AS protocol to conventional care due to intraoperative cerebrospinal fluid leakage (one case) and an unsatisfying post-anesthetic discharge score (one case). Complications included transient and reversible mild postoperative nausea and vomiting [visual analog scale (VAS) score <3], headache (VAS score <3) after the operation or early after discharge. No patient was readmitted. Our results supported the safety and efficacy of the AS protocol for pituitary adenoma patients undergoing EEA resection among eligible patients, and further evaluation of this protocol in controlled studies with a larger sample size is warranted. Current advances in perioperative surgical concepts and technologies promote the advent and prevalence of ambulatory surgery (AS) in several surgical fields. The use of AS has accounted for >60% of all surgeries performed in the United States, with improved patient satisfaction and reduced costs compared to traditional surgery 1. In the field of neurosurgery, although attempts had been made to resect supratentorial brain tumors and clip unruptured cerebral aneurysms on an outpatient basis 2,3. AS remains not widely adopted. The endoscopic endonasal approach (EEA) for the resection of pituitary adenomas has gained increasing acceptance over the past few decades. Evidence suggested that EEA features shorter operative time, minor surgical