Background: Polycystic ovarian syndrome (PCOs) is a common endocrine disorder that is associated with negative metabolic, reproductive, endocrine, and psychological consequences among women in reproductive age. Many girls with chronic menstrual irregularities could have PCOs. This study aimed to assess the levels of knowledge for female nursing students regarding polycystic ovarian syndrome, at south valley university. Subjects and Methods: A descriptive cross sectional design was used to achieve the objective of this study. Setting: The study was conducted at faculty of nursing, south valley university. Sample: convenient sample on 260 female students at different grades. Tool: Data was gathered using a structured interview questionnaire developed by investigator. Results: The results showed that 1.2%, 45.4%, 53.45% of the female students had poor, moderate, and good knowledge respectively. There were a high significant relation between total score of female students knowledge and their Grade (P= 0.001) and pre-university qualifications. Also, there is highly statistical significant difference between total score of female students and those who had studied maternity course. Conclusion: more than half of the female students had good knowledge regarding Polycystic Ovary Syndrome (PCOs). Recommendation: promotion of health regarding PCOs and modifications of lifestyle. – Educational program for adolescent girls about PCOs and encourage modifications of their lifestyle.