Abstract: Objective To provide the evidence for aeromedical support by observing the characteristics of disease spectra in permanently grounded helicopter aircrews. Methods Medical record data about 62（85 cases/time） grounded helicopter aircrews admitted to our hospital from January 2001 to December 2010 were collected and stratified according to their disease,involved specialty and age.The data were compared with the reported findings in fighter pilots. Results The top 10 diseases causing permanent grounding of helicopter aircrews were headache,cervical and lumbar spine disorders,ground syncope,neurosis,hypertension,post-traumatic brain syndrome,viral hepatitis,chronic nephritis,ametropia,and episodic vertigo.The proportion of grounded helicopter aircrews with air syncope was lower than that of fighter pilots（χ²=7.02,P＜0.01）.However,no significant difference was observed in the proportion of the other 5 diseases.The proportion of 23-30 years old grounded helicopter aircrews was higher while the proportion of 35-39 years old grounded helicopter aircrews was lower than that of fighter pilots（χ²=9.11,P＜0.01;χ²=5.39,P＜0.05）.No significant difference was found in the proportion of grounded helicopter aircrews at different ages. Conclusion The proportion of grounded helicopter aircrews with a poor acceleration tolerance is lower than that of fighter pilots.The proportion of grounded helicopter aircrews and fighter pilots is different at different ages.The leading diseases causing permanent grounding of helicopter aircrews and fighter pilots are headache,cervical and lumbar spine diseases,ground syncope,neurosis and hypertension.