Study about political attitude and gender differences seems necessary, because of essential role of the political attitude in political behavior, and importance of gender differences for researchers in the field of women's studies. Considering to this scientific necessity, this study investigates the role of university reference groups in college students' political attitudes according to gender differences. This descriptive- analytic study was carried out using survey method. The statistical society is comprised of all the undergraduate, master's and PhD students at University of Tehran. 400 students (226 boys and 174 girls) were selected through availability sampling. Students have responded to a researcher- made questionnaire. The main hypothesis of this study is: there exists gender differences in relationship between the level of interaction with the reference group (including college professors, student organizations and the university students) and students’ political attitudes (in three dimensions: cognitive, affective and action). For data analysis, SPSS was used. The results showed that there are gender differences in all three dimensions of political attitudes. The findings also suggest that university friends and then college professors have the most important role in changing political attitudes of the students.