Background: Infertility is a major public health challenge worldwide. Recently there is a rising trend of obese couples presenting in the infertility clinics. There is an established association between female obesity and infertility but a similar link is yet to be proven in men. Elevated body mass index (BMI) has been reported to affect semen quality by different authors. There is however no consensus on the role of elevated BMI on semen quality as well as the semen parameter it affects. Hence the need for this study in our environment to determine the effect of elevated BMI on semen quality in male partners of infertile couples. Objectives: To determine the proportion of male partners of infertile couples with elevated BMI with normal and abnormal semen quality as well as the pattern of semen parameter abnormalities on semen analysis. Study Design: A prospective cohort study to determine the effect of elevated BMI on semen quality in male partners of infertile couples. Method: Two hundred and six consenting men who met the inclusion criteria were recruited for the study. Selected participants had their weights (kilogram) and heights (metre) measured. Their body mass indices (kilogram/metre2 ) were assessed and grouped into normal weight (18.5-24.9kg/m2 ) and elevated BMI (≥ 25kg/m2 ). Their semen samples were collected by masturbation after a recommended 3-5 days of abstinence and semen analysis done to assess the semen quality. Semen quality was assessed based on sperm count, percentage motility and morphology. Data entry and analysis were done using SPSS statistical software version 20. Statistical analysis was performed using Chi-square test. Relative risks and confidence interval were employed as appropriate. Statistical significance was set as P <0.05.