Objective: This study is performed to examine the attitudes regarding marriage, family, and premarital sex among the students of different majors. Participants: Four hundred fifty-seven students from four majors studying Medical Sciences, Arts, Humanities, and Mathematics/Engineering within the age range of 18- to 24-year old. Method: Participants were selected from different universities in Tehran using stratified nonprobability sampling method. Attitudes of our participants were examined using the premarital sexual, marital, child-rearing, and family attitude Survey and demographic variables, including major, age, gender, religious beliefs, family socioeconomic level, and marital status were evaluated. Results: Most of the results of the survey showed significant differences between different majors. Art students were open to premarital sex more than other students and believed that premarital sex would cause no harm in reputation for females. By contrast, Medical sciences students had the highest agreement regarding the bad influence on the reputation of females because of premarital sex and also regarding men's tendency to virgin girls. Art students mostly approved the acceleration of the divorce process while the highest disapproval in this regard was reported from Medical sciences students. Conclusion: Art students' beliefs about premarital sex were more liberal, while Medical sciences students' beliefs in this matter were more conservative.