Background:Elective surgical case cancellation refers to any elective surgical case that is bookedrninto the operation theatre list on the day prior to surgery, but is not operated upon as scheduled.rnElective surgical case cancellation is common and can have significant adverse effects. The cancellationrnof planned surgeries causes prolonged wait times, harm to patients, and is a waste of scarce resourcesrnin countries like Ethiopia. Cancellation of scheduled surgery leads to operating theatre under-occupancyrnand is recognized as a major cause of emotional trauma to patients and their families.rnReasons for cancellations are complex and many; they are as unique as they are similar.rnObjective:To determine the point prevalence of elective surgical case cancellations and the reasonsatrnthe major OR in TikurAnbessa specialized hospital from June 1 to October 31, 2017 G.C.rnMethod:This was a prospective cross sectional study of the operation theatre list over a period of fivernmonths (June 1,2017-October 31, 2017). All patients scheduled to undergo elective surgeries at thernmajor OR of the hospital from June-October 2017 were included. Data was collected by using pretestedrnstructured questionnaires and an assigned OR staff was recording the cancelled cases in real time. Thernassigned staff has confirmedthe cancellation reason and added additional necessary explanation.rnData wasentered in to SPSS version 20 for analysis. The result of study was explained by narratives,rntables andgraphs.rnResults:For the given study period, 1904 elective surgeries were scheduled to be performed at thernmajor OR of TASH, of which 627 cases (32.9 %) were cancelled on the day of surgery. The average agernwas 37 years, with male to female cancellation ratio of 1.07:1. The main reasons for cancellation werernmanagement/facility related (45.9%), shortage of time related (31.4%), and Workup/medicalrnconditionrelated (9.7%). Neurosurgery experienced the most cancellations (27.4%), followed by generalrnsurgery (16.3%).rnConclusion: This study found out that the cancellation of elective surgical operation on thernscheduled day of surgery was very significant. Most of the reasons were deemed avoidableandrncommonest were management/facility related followed by shortage of time related.rnRecommendation:Determining an easily avoidable contributors to the cancellations is an essentialrnfirst step to developing appropriate interventions to improve OR efficiency.Implementation of patientrnpreoperative assessment should be applied. A team approach ensuring presence of policies andrnprocedures for improving and ensuring realistic scheduling of patient lists, reducing time spentrnpreparing and cleaning the operating room and better handling resources should be applied.