The rupture of the round window membrane is a special form of traumatic inner ear deafness. Because of the changing pressure levels, divers are at risk of developing such a membrane rupture, especially if tube function is disturbed. As the popularity of diving as a sport increases, ENT specialists have to deal with diving related problems increasingly frequently.Seven cases of divers are presented in whom a tympanotomy was performed following the diagnosis of a rupture of the round window membrane. The symptoms and intraoperative findings are discussed and the otologic and diving literature is reviewed. Following a case report, the pathophysiology, clinical symptoms and differential diagnosis of round window ruptures are discussed controversially. Possible therapeutical consequences are described.None of our patients exhibited the classical triad of deafness, tinnitus, and vertigo as described in the diving literature. The leading symptom in our patients was the loss of hearing; only two patients had vertigo. Tinnitus was found in half of the patients. Intraoperative a rupture of the round window membrane was presumed in five divers.If disturbance of inner ear function does occur concurrently with diving, a rupture of the round window membrane must be considered. An otologic examination must be performed in any diver with a loss of hearing and/or signs of a barotrauma of the middle ear. After differential diagnosis to exclude other possibilities, a tympanotomy to cover the round window membrane should be performed if symptoms persist more than 24 hours.