The association between infertility and sperm disomy is well documented. Results vary but most report that men with severely compromised semen parameters have a significantly elevated proportion of disomic sperm. Recently, many studies have found a decrease in semen quality due to occupational hazards . Generally, occupational exposures have been divided into physical exposures (heat and radiation), chemical exposures (solvents and pesticides), psychological exposures (distress), exposure to metals and welding. This study aimed to determine the incidence of chromosomal abnormalities andsperm disomy in infertile men with idiopathic severe oligoasthenoteratozoospermia (OAT) and in idiopathic infertile males with normal semen parameters  who were exposed to various environmental factors . Thirty male subjects were included in this study ten infertile men with severe OAT ( group 1) , ten with idiopathic infertile men with normal semen parameters ( group 2) and ten fertile male as control (group 3). The participants of both groups (group 1 and group 2) were exposed to various hazardous environmental factors such as physical and chemical factors and personal habits .Through clinical examination and lab investigations semen analysis and hormonal assays were done . Cytogenetic studies were done that included FISH assessment of sperm using cocktail X,Y prope to detect  the disomic level of chromosomes X and Y .Total disomy percent showed non significant difference within the three groups. Total disomy percent showed significant positive correlation with the number of environmental factors in severe OAT patients and idiopathic infertile patients. Age showed non significant positive correlation with total disomy percent within the three groups.