Background: Polycystic ovary syndrome (PCOS) is a heterogeneous disorder characterized by a diverse collection of reproductive and metabolic abnormalities. kisspeptin (KISS) is novel peptides associated with regulation of metabolism, food intake, puberty and reproduction. The aim of the present study was to estimate KISS level in patients with PCOS, and to evaluate the possible relationship between KISS level with anthropometric measures as well as clinic-morphological features of PCOS. Materials and methods: cross section control study enrolled 90 control group and 105 patients with PCOS and they were stratified according to their body mass index (BMI) to; underweight (n ¼ 9, BMI ˂19), normal weight (n ¼ 25, BMI ¼ 19.1e25), over weight (n ¼ 34,BMI ¼ 25.1e30), obese grade I (n ¼ 12, BMI ¼ 30.1e35) , obese grade II (n ¼ 13, BMI 35.1e40) and obese grade III (n ¼ 12, BMI˃40).Circulating KISS levels were measured using ELISA. Results: Our results revealed that, KISS levels were higher in PCOS patients compared to controls. Among PCOS group, there were significant lower level of KISS levels in underweight, overweight and obese compared to normal weight group. Even more importantly, KISS levels decreased with increasing of BMI as the following, grade I, grade II and grade III. Moreover, it was negatively correlated to anthropometric measures, glycemic, lipid profile and positively correlated the phenotype characteristics of PCOS. Linear regression test observed that hirsutism score, HOMA-IR and LH were the main predictors of KISS levels in PCOS. Conclusion: circulating KISS is an important regulator of body weight and reproduction especially in PCOS women.