This study explored the working environment of airline cabin crew and enhance service quality by examining the relationship between flight fatigue and psychological service degradation factors, and flight stress as a moderating variable. A conveinence sample of 453 cases were analyzed. The study participants were domestic airlines' cabin crews who were recruited through SNS, from Jan. 2020~May 2020. It was found that there is a statistically positive(+) relationship between flight fatigue increase and psychological service degradation factors, and flight stress. Consequently, it was found that route, physical, human, and unexpected factors increasing flight fatigue of cabin crews have a positive effect on flight stress. It was also found that flight stress affects psychological service degradation, and by examining the relationship between the fatigue increase and psychological service degradation factors, and stress moderator, it was found that fatigue increase factors and flight stress affect psychological service degradation. The findings suggest that service worker, such as airline cabin crew experience emotional dissonance due to the customers' improper service requirements and the organizational norms. This study is an initial inquiry into the relationship between the cabin crew's flight stress factors and psychological decline.