Abstract: Objective To investigate the aural air-pressure function in helicopter aircrews. Methods Medical history of 158 helicopter aircrews was recorded. The helicopter aircrews underwent electric auriscopy, pure-tone test, tympanometry, rhinoscopy and nasal endoscopy in August 2013. Those without contraindications for hypobaric chamber test were allowed to enter the chamber which was elevated to 4 000 m at the velocity of 15 m/s for 5 min and then descended to the ground at the velocity of 5 m/s. The aircrews recorded their subjective symptoms when the chamber was elevated to 1 000 m and descended to 1 000 m at each time. The findings of electric auriscopy, pure-tone test and tympanometry after they came out of the chamber were compared with those before they went into the chamber. Results Of the 157 aircrews (314 ears) who underwent hypobaric chamber test, 75 (75 ears) presented with symptoms such as aural fullness and tenderness which exaggerated when the chamber was descended to 3 000-1 000 m, 19 (30 ears) presented with degree Ⅱ tympanic membrane hyperemia and 1 (1 ear) presented with degree Ⅲ tympanic membrane hyperemia, 20 (31 ears) presented with mild or moderate conductive hearing loss, 19 (22 ears) showed a C-type curve and 3 (3 ears) showed a B-type curve, 10 (17 ears) were diagnosed with abnormal aural air-pressure function, accounting for 6.37% and 5.41% respectively. Of these 10 aircrews, 6 (12 ears) were diagnosed with mild abnormal aural air-pressure function, 1 (1 ear) with moderate abnormal aural air-pressure function, 3 (4 ears) with severe abnormal aural air-pressure function. Conclusion The general aural airpressure function is good in helicopter aircrews. However, a very small number of helicopter aircrews have not mastered the key points to open their auditory tube and should thus be effectively strained.