Hyaluronic acid is the most abundant mucopolysaccharide in connective tissue. Because of its high viscous elasticity, it lubricates joints and can hold cells together in the intercellular spaces in connective tissue. The administration of exogenous hyaluronic acid can increase the repair potential of damaged tissue. A study was conducted to verify whether or not hyaluronic acid enhances the repair process in perforations of the tympanic membrane and to evaluate the quality of the tympanic membrane after healing. The 17 patients, aged 22 to 63 years, had small, medium, or large perforations of the tympanic membrane that were treated locally with sodium hyaluronate until a reduction in the area of the perforation was observed. The patients were examined with an otomicroscope and completed evoked-response and impedance tests. Of the 17 perforations treated, 12 (eight small and four medium) healed after two to 11 days of treatment. None of the large perforations healed. Treatment was less effective in patients with secretions from the middle ear. In the 12 patients whose perforations were healed, three months after treatment the tympanic membrane was normal in most cases; hearing threshold, measured with the evoked-response test, had improved; and the tympanometric curve, measured with the impedance test, had returned to normal.