Ninety subfertile couples were involved in the present study during their attendance at fertility clinic at Al-Sadder teaching hospital in Al- Najaf/Iraq throughout a period from March 2016 to January 2017. Details history and physical examination were done for every subject participated in this study. Body Mass Index (BMI) was measured for all male participants that divided according to it into three categories including normal weight, overweight and obese males. The objective of this study was to investigate whether increased male BMI has any impact on sperm parameters or on seminal antioxidants. Main results of this study revealed that there was a significant differences (p<0.05) in sperm parameters and in the antioxidants levels among different male BMI categories. With increasing male BMI there was a decrease in sperm parameters and in seminal antioxidants levels. It was concluded that increased male BMI have a negative impact on different sperm parameters including (concentration, motility, morphology and volume) and on the levels of seminal antioxidants including (Glutathione, catalase and Super Oxide Dismutase (SOD)).