Epiglottic entrapment is a condition in racing horses, associated with abnormal respiratory noises and exercise intolerance. Epiglottic entrapment has been linked to both poor and superior athletic performance, leading to concerns regarding whether surgery is indicated, and whether surgical correction may have a deleterious effect on future race performance. The objective of the current study was to assess the race-day performance of horses racing with epiglottic entrapment and the effect of surgical correction on performance outcomes using an intra-oral technique in anaesthetised horses. A case-control study was conducted at the Singapore Turf Club from 2008 to 2011. Controls were selected 1:1 to cases, based on Malaysian Racing Authority number. The performance of horses racing with epiglottic entrapment was recorded and post-surgery race performance was described. Further, post-surgery race performance was compared between cases and with non-case controls. Twenty horses raced with epiglottic entrapment were retrospectively enrolled. There was a significant difference in racing performance in case horses racing with and without epiglottic entrapment (P