Background: Varicocele is an abnormal dilation of the testicular veins in the pampiniform plexus and characterized by retrograde blood flow in the internal spermatic veins due to incompetent or absent valves. It is considered one of the main causes of male factor infertility. Sperm DNA integrity is essential for in vivo and in vitro fertilization, and varicocele causes a progressive decrease in sperm quality . Objective: To study the impact of varicocele on semen quality and sperm DNA integrity. Patients, Materials and Methods: Twenty patients with varicocele and 20 men without varicocele were assigned into two groups in the Out-Patient Clinic of Urology in Al-Kadhimya Teaching Hospital . Semen was collected from both groups and the rate of sperm DNA fragmentation assessed by the "Comet assay" and categorized to 4 classes. Class I (no DNA fragmentation), class II (little DNA fragmentation), class III (meaningful DNA fragmentation), and class IV (high DNA fragmentation) . Results: No statistically significant differences were found between the varicocele and control groups with respect to age. Men with varicocele had significantly higher ejaculate volume, lower sperm concentration, and lower progressive motility, and showed more abnormal morphology than men in the control group. The Varicocele group showed a lower percentage of sperm with little DNA fragmentation (class II) and a higher percentage of sperm with DNA fragmentation (class IV), than the control group. Conclusions: Compared with men without varicocele, men with varicocele had a higher percentage of cells with DNA fragmentation .