Background: The reported prevalence of infertility in Pakistan is 21% of which 35% is contributed by male factor. Male infertility has multifactorial etiologies ranging from modifiable to genetic risk factors. Among all the risk factors that may account for male infertility, obesity is one of the emerging public health problems. Therefore, the aim of the study was to determine the association of obesity with infertility in Pakistani men.Methods: We conducted a case control study. Cases were men with impaired semen parameters and controls did not have impaired semen parameters.Results: The final multivariable logistic regression model after adjusting for the effect of other variables revealed that with every 1 kg/m2 increase in BMI the odds of being infertile was 6% higher as compared to being fertile (aOR = 1.06; 95% CI = 1.01, 1.11). Moreover the odds of having education of higher secondary or above was 3 times greater among cases as compared with the controls (OR = 3.10; 95% CI = 1.66, 5.77). Furthermore the odds of having previous medical conditions increasing the risk of infertility was higher among cases as compared with the controls (OR = 3.07; 95% CI = 1.63, 5.79).Conclusion & recommendations: This study indicates that obesity is an important risk factor for male infertility. Moreover our findings also indicate that higher educational status and previous medical conditions are also associated with male infertility. Thus awareness can be raised through treating physicians and public health messages