BACKGROUND:Infertility constitutes a major part of the health problems in our society and male infertility is a serious problem all over the world. Nutritional deficiency of trace elements like zinc play a role in male infertility as zinc plays an important role not only in normal testicular development, but also in spermatogenesis and sperm motility. OBJECTIVE:To evaluate and compare the concentrations of zinc in blood and seminal plasma with semen parameters among fertile and infertile Nigeria men. STUDY DESIGN:A prospective case-control study. SUBJECTS AND METHODS:Eighty five men with primary infertilitywhose partners had been fully investigated and found essentially normal, aged 20-55 years were enrolled as cases.The control group were made up of eighty five men with normozoospermia whose partners had spontaneous conception. After semen analysis the cases were further grouped asoligozoospermic (n=64), asthenozoospermic (n=13) and azoospermic (n=8).All the semen samples were analyzed according to WHO 2010 criteria. Blood and seminal plasma concentration of zinc were determined by microwave plasma-atomic emission spectrophotometer. The results were coded,fed into the computer and analyzed using theStatistical Package for Social Sciences (SPSS)IBM version 19. Chi square test was used to compare categorical variables and t-test was used to compare means. Mann Whitney U test and Kruskal wallis test were used to compare median of two or more than two numerical variables respectively.Spearman rho correlation was used to determine correlation between numerical variables that were not normally distributed. For all statistical test p was considered significant if it was less than 0.05.