This study analyzes the socioeconomic factors behind HIV prevalence and risky sexualrnbehaviors using the 2000 and 2005 Ethiopian Demographic and Health Surveys. Thernstudy also examines changes in risky sexual behaviors occurred between the two surveys.rnEconometric models used in the study include Hickman probity model for HIVrnprevalence, Proportional Hazard model for age at first intercourse, and pro bit model forrncondom use and number of sexual partners. According to the results of Heckman Pro bitrnmodel, Women who attend higher education are at lower risk of HIV infection, whereasrnthose who attend primary education are at higher risk. However, education appears tornhave insignificant effect for men's HN infection. On the other hand, wealth has arnprotective effect against HN for men, whereas women of highest wealth quintile are atrnhigher risk of HIV infection. Marriage for women and urban residence for both sexesrnconsistently predicts higher HN prevalence .rnWith regard to the effect of education and wealth on risky sexual behaviors, both factorsrnare associated with lower risky behaviors and the protective effects of these factors arernmore apparent in 2005 data. The exception 10 this fact is that education increases hazardrnrate of early sexual initiation for males in both survey data. Marriage and urbanrnresidence significantly increase risky behaviors, with exceptions that marriage reducesrnmultiple partnerships and urban residence increases the probability of condom use .rnChanges ill sexual behaviors are more pronounced among men than women . Compared,rnto the earlier survey (2000), men have experienced later age at first sex, lowerrnprobability of multiple partners and higher probability of condom use in the later surveyrn(2005). With exception of lower probability of multiple partners, women, however,rnexhibited earlier sexual initiation in 2005 than in 2000. Hence, the study assures thatrnthere are still opportunities to reduce HIV prevalence by devising policies which promoternbehavioral changes among women and the poor and illiterate society.