Background: energy availability influences reproductive fitness.the activity of reproductive axis is sensitive to adequacy of nutrition and stores of metabolic reserves.the adipocyte derived hormone,leptin,is postulated to reflect the state of nutrition and energy reserves and acts as a metabolic link to reproductive system.The present study investigated the serum leptin concentration in normal fertile and infertile men and its relation to testicular function. Methods: this work includwd eighty male subjects,they wew divided according to their sperm count into three groups:azoospermic group (n=30),oligozoospermic group (n-30) and control group ( normal fertile;n=20).Different variables were studied for all included subjects;age,body weight,body mass index,serum total testosterone,serum leptin level,semen analysis,varicocele and smoking. Results: There was statistically significant positive correlation between serum leptin and body weight,body mass index and age. There was statistically significant inverse correlation between serum leptin and serum total testosterone. Azoospermic group and Oligozoospermic group have higher serum leptin level than control group. Serum leptin level was higher in subjects without varicocele in azoospermic group and oligozoospermic group . Conclusions: The results of this study are suggestive of a link between leptin and male reproduction