The current WHO 2010 manual for human semen analysis defines leukocytospermia as the presence of peroxidase-positive leukocytes at a concentration >1×10
6
/mL of semen. Granular leukocytes when activated are capable of generating high levels of reactive oxygen species in semen resulting in oxidative stress. Oxidative stress has been correlated with poor sperm quality, increased level of sperm DNA fragmentation and low fertility potential. The presence of leukocytes and pathogens in the semen may be a sign of infection and/or localized inflammatory response in the male genital tract and the accessory glands. Common uro-pathogens including
Chlamydia trachomatis
,
Ureaplasma urealyticum
,
Neisseria gonorrhoeae
,
Mycoplasma hominis
, and
Escherichia coli
can cause epididymitis, epididymo-orchitis, or prostatitis. The relationship between leukocytospermia and infection is unclear. Therefore, we describe the pathogens responsible for male genital tract infections and their association with leukocytospermia. The review also examines the diagnostic tests available to identify seminal leukocytes. The role of leukocytospermia in male infertility and its management is also discussed.