Polycystic ovarian syndrome (PCOS) as a common cause of anovulatory, is associated with glucose metabolic abnormality, hyperinsulinemia and obesity, features which are related to leptin and its receptors. However, there is still debate over the link between leptin and endocrine and metabolic factors in PCOS. The present study aim to compare both obese/overweight and normal/underweight PCOS and healthy women regarding anthropometric and endocrine parameters. Also, estimate inter-relationship of serum leptin levels with anthropometric and endocrine parameters. This is a case-control study including 150 PCOS women and 100 control subjects. Anthropometric indices were measured for each subject.  Lipid profile, fasting glucose, insulin, gonadotropin hormones, testosterone and serum leptin were estimated. Insulin resistance through HOMA-IR model and insulin sensitivity through (QUICKI) were calculated. Students t-test and two-way ANOVA were used for analyzing the differences between groups. Pearson (r) correlation coefficient was used to assess the correlation between serum leptin and the independent variables. Waist circumference was increased in normal/underweight PCOS group compared to normal/underweight control group. Fasting glucose and insulin, HOMA-IR, QUICKI and serum leptin levels were significantly increased in obese/overweight PCOS group compared to obese/overweight control group. Strong significant correlation was observed between serum leptin levels and increased BMI, LDL, fasting glucose, fasting insulin, HOMA-IR and hypotension. Serum leptin levels showed strong correlation with metabolic syndrome risk factors especially glucose metabolic abnormality in PCOS women compared to control.