Objective:To explore the relationship between defense style and personality traits of college students.Method:196 college student were assessed with DSQ, EPQ and 16 PF.Results:Students with higher extraversion and liveliness were more inclined to adopt mature defense, while students higher on neuroticism, vigilance, apprehension, tension were inclined to adopt immature or middle defense. Students with higher psychoticism, sensitivity adoppted immature defense to cope emergency, students with higher social boldness and openness to change were more likely to adopt mature or middle defense.Conclusion:Personality trait is one of the factors having influence on defense style.