Objective: 1) To estimate the prevalence of primary infertility in the study population. 2) To describe the socio demographic characteristics prevailing among couples with primary infertility in the study population. 3) To identify the probable medical conditions associated with primary infertility. Design: Cross- sectional descriptive study. Setting: Rural field practice area of tertiary hospital, Bangalore. Sample: Complete enumeration of entire Kumbalgodu Primary Health center area covering 26, 190 populations. Methods: In depth interview using a pretested pre-structured questionnaire was conducted for a period of 18 months (January 2012 to August 2013) to enumerate all couples with primary infertility in the entire Kumbalgodu Primary Health Centre area. Review of investigation reports available with couples at the time of study. Results: In the present study area, prevalence of primary infertility was 4.5%. The most common cause of primary infertility among females was pelvic inflammatory disease followed by polycystic ovarian disease and among males it was oligospermia. Conclusion: This study has yielded important information regarding the prevalence and risk factors influencing primary infertility. Efforts to raise awareness in the population about the causes of primary infertility are needed and facilities should be made available for early diagnosis and treatment.