Background: The Fibroblast associated (Fas) system in the testes has been identified as a key regulator of apoptosis, a process that greatly influences the germ cell population of the testes. Objective: This study measures the level of soluble Fas Ligand (sFasL) in the semen of oligozoospermic men evaluating the association between seminal plasma sFasL and spermatogenesis. Methods: A total 58 oligozoospermic men and 29 normal volunteers were included in this study. semen was evaluated according to World Health Organization 2010 standard parameters. sFasL was measured using ELISA enzyme immunoassay for quantitative determination of sFasL. Results: s FasL level was found significantly higher (P< 0.01) in seminal plasma of oligozoospermic men, with weak correlation of the level of this marker with the degree of severity of oligozoospermia. Conclusions: The apoptotic marker, sFasL is a novel marker found in the seminal plasma of oligozoospermic men. It's level is higher in cases of oligozoospermia regardless of its severity.