Background: One of the major concerns among the male reproductive health is the inability to achieve parenthood even after regular unprotected intercourse. The efficiency of the sperm selection techniques is expressed as the concen-tration of spermatozoa with normal motility. Discontinuous density gradient centrifugation (DGC) method widely used over the last decade due to effec-tiveness and reproducibility in recovering most motile sperm, which separates sperm based on their motility, size, and density differential. Glutathione act as an amino acid donor during spermatogenesis. If the levels of glutathione are too low during spermatogenesis, the number of mature and morphologically normal spermatozoa generated will be decreased. Objectives:The aim of this study was to assess the beneficial role of TAD 600mg Glutathione combined with DGC technique for activation of human sperm of asthenozoospermic, oligozoospermic and normozoospermic subjects compared with the DGC technique alone. Patients, Materials and Methods:Sixty males were involved in this study, di-vided into three groups, (twenty asthenozoospermic, Twenty oligozoospermic and twenty normozoospermic subjects)during their attendance to the Infertility Clinic at High Institute for Infertility Diagnosis and Assisted Reproductive Tech-nologies; Al-Nahrain University. Semen samples were obtained, and seminal fluid analysis was assessed. Each semen sample was divided into three parts. The first part prepared as in vitro sperm characterization before activation, the second part using density gradient centrifugation technique, while the last part prepared using density gradient centrifugation combined with TAD 600mg Glu-tathione. Results: After in vitro sperm activation for asthenozoospermic, oligozoospermic and normozoospermic samples a significant increase was observed in the sperm function parameters including sperm concentration, motility and morphological-ly normal sperm percentage as compared to pre-activation using combined tech-niques (density gradient centrifugation and TAD 600mg Glutathione) as com-pared to DGC technique alone. Conclusions:TAD 600mg Glutathione combined to the DGC technique was found to give higher significant results on sperm function parameters (sperm concen-tration, motility and morphology) when using a low quality of semen samples such as decreased sperm motility as compared with DGC technique alone.