Purpose: This study was done to identify factors that affect sexual permissiveness in college students. Methods: A descriptive design was used with 380 college students who completed a questionnaire about self-esteem, parents-adolescent communication, friend`s sexual attitude and sexual permissiveness. Results: The sexual permissiveness showed significant differences for the variable: grade (F=0.51, p=.002), gender (t=7.28, p<.001), age (F=14.72, p<.001), religion (t=4.97, p<.001), residence type (F=4.75, p=.009), number of call with parents (F=3.56, p=.030), number of viewing pornographic video (F=36.05, p<.001), number of viewing pornographic magazine (F= 47.90, p<.001), status of dating (t=3.62, p<.001), number of sexual intercourse (F=14.51, p<.001), and experience of sexual intercourse (t=13.00, p<.001). There was a positive correlation between the friend`s sexual attitude and sexual permissiveness (r=.64, p<.001). The variables such as friend`s sexual attitude, experience of sexual intercourse, the number of watching pornographic video, educational system, religion, and the number of calls with parent explained 52% of the variance in sexual permissiveness. Conclusion: The results of this study indicate that it is necessary to develop sexual education program for college students considering their level of sexual permissiveness and their friend`s sexual attitude.