Background & Objectives: Population and family planning course is given for university students in order to promote students' knowledge and attitude and improve decision ability of students on fertility, sexual health, and family planning. This study aimed to investigate the effect of population and family planning course on knowledge and attitude of Mohaghegh Ardabili university female students toward related subjects and to determine attitude of students about instructor's gender. Methods: In this cross-sectional study, all the female students of Mohaghegh Ardabili University (189 individuals) were studied before and after teaching "population and family planning" course using researcher made questionnaire and data were analyzed using SPSS 12. Results: Results showed that 88.9% of students aged from 20 to 25 years. 12.7% were married and 2.1% of married students had only one child. There were statistically significant differences between knowledge and attitude of students before and after teaching (p<0.05). The majority of female students (99.5%) preferred female teachers. From the student point of view first year of the study is the best time for this course. Conclusion: According to the results of this study, teaching family planning courses by different, appropriate, and continues methods in universities is the most important approach to increase student knowledge and attitude and motivate them for active cooperation in family planning programs.