The Catholic Church in Nigeria offers premarital HIV screening to couples, yet instances of voluntary screening are rare in southeast Nigeria. This study examines the contribution of such tests to HIV detection, and evaluates the prevalence of HIV infection in southeast Nigeria among couples who are planning to marry. Out of 858 individuals (or 429 couples) tested for HIV, 52 individuals were found to be HIV-positive (overall prevalence 6.1%), and females were marginally more affected than males. In both sexes, prevalence was higher in younger age groups. Prevalence among adolescent females was 10.7%. Although no male adolescents were screened, prevalence for the group aged 20 to 29 years was 6.3% for females and 10.8% for males. The prevalence estimate was slightly higher for rural dwellers (6.2%) than for urban residents (5.9%), but this was not statistically significant. We propose that screening apparently healthy individuals, such as couples intending to marry, and who are otherwise not members of a group considered at high risk for HIV infection, can serve an important role in HIV detection in the general population.