Abstract: Personality traits, nurtured by manifold individuality demands, is the reaction formulary formed by behaviors that are determined by characters. To cultivate college students to have moral integrety is to make their behavior formulary fit to the social demands in various environments. This article starts with the personality demands and personality judgment, discussed about the environmental factors influencing the character behaviors of college students, and put forward the countermeasure of cultivating good personality traits of college students.