In Swaziland the risk of getting HIV infected is significantly higher among young women compared to young men. These differences cannot be explained by anatomical and hormonal factors that make young women particularly vulnerable to HIV infection. In this article the results of a secondary analysis of the Swaziland Demographic and Health Survey 2006-2007 data is described. In particular, trends and variability in age differences between young men and their female sexual partners are explored. In addition the magnitude of the age difference between sexual partners and the association with consistent condom use is examined.