목적: Since Eustachian tube (ET) plays an important role in the development of middle ear disease, evaluating the function of ET is important. Valsalva maneuver is frequently used, but does not reflect the physiological function. Inflation-deflation test assess both active and passive function of the ET, so it can reflect the physiological function. In our clinic, we use device named EustachiTM to evaluate ET. In this study, we evaluated ET in patients with perforated eardrums using Valsalva maneuver, inflation-deflation test and EustachiTM to evaluate the efficacy of EustachiTM in assessing ET function. 방법:51 dry perforated eardrums were selected. Patients were divided into 3 groups according to the result of the inflation-deflation test; Type A, ET opens in both positive and negative pressure; Type B, ET opens in either positive or negative pressure; Type C, ET dose not open in neither positive nor negative pressure. All patients performed Valsalva maneuver and EustachiTM application. Techniques were statistically analyzed and compared. 결과:When analyzing whether Valsalva was possible according to the type of inflation-deflation test, there were statistical differences when comparing type A, B and type A, C(p=0.000, 0.024). There was no statistical difference between type B and C(p=1.000). When analyzing the result of EustachiTM according to the type of inflation-deflation test, there was no statistical difference between type A and B(p=1.000), while there were statistical differences when comparing type A, C and type B, C(p=0.048, 0.030). 결론:Compared with the results of inflation-deflation test, EustachiTM can evaluate ET more physiologically than Valsalva maneuver.