Posterior ankle impingement syndrome (PAIS) is a clinical condition characterized by pain in the posterior aspect of ankle on performing activities requiring extreme plantar flexion. The impinging lesion could be bony and/or soft tissue. The operative treatment aims at removing the impinging lesion either by open or endoscopic surgery. The later has been shown to have benefits of early return to sports, better cosmesis, less wound complications. We report a case of a 19 year old footballer with PAIS secondary to Os Trigonum. The patient complained of pain on performing running and on kicking football. Conservative treatment in form of NSAIDS, rest, physiotherapy modality use could not ensure pain free return to sports.The patient was managed using endoscopic excision of the Os Trigonum followed by aggressive rehabilitation. The patient returned to competitive football at the end of 14 weeks after surgery. There were no wound complications. AAFOS score had changed from 73 to 100 and NPS scale showed pain score reduce from 7/10 to 1/10. We concluded that endoscopic management of PAIS to remove the impinging lesion is a minimally invasive technique that ensures early return to sports, good cosmesis, less risk of wound complications and good patient satisfaction.