The semen quality of 479 men in infertile marriages, who attended the infertility clinic of OOUTH, Sagamu between May 2004 and April 2009 were analyzed. The semen samples were physically examined, microscopically analyzed and aerobically cultured. The result showed that out of 51.5% oligospermic cases recorded, 39.8% could be classified severe. Cryptozoospermia were diagnosed in 72 (15%) cases. Bacteriospermia and Necrozoospermia were found in 149 and 6 cases respectively. The predominant organism isolated was Staphylococcus aureus (50.32%) while Neisseria gonorrhoea was isolated in only 2 cases. Highest infection of 62.4% was noticed among the group with 1%-19% motility. From the studied population, 8.8% were azoospermic. The commonest morphological defects were pin and ragged heads (48%). It is therefore obvious that the assessment of semen quality remains one of the important steps in infertility interventions.