Introduction: Youth who begin early sexual activity are less likely to use condoms and more likelyrnto have multiple partners and early child bearing which intern brings about higher rates of maternalrnand child morbidity and mortality. Higher rates of unintended pregnancy, HIV/AIDS and otherrnsexually transmitted infections among youths make it fundamental to understand factors associatedrnwith early sexual initiation in a wider perspective for designing and implementing effectiverninterventions.rnObjective: To assess the magnitude of early sexual initiation and its associated factors amongrnyouths in Addis Ababa, April 2014rnMethodology: A quantitative cross sectional facility based study supplemented with qualitativernenquiry was conducted on a sample of 622 youthâ€™s attending youth centers in Addis Ababa. Arnsystematic random sampling technique was applied to select the study participants. A pretestedrnstructured questionnaire was used to collect quantitative data while focus group discussions usingrnsemi-structured interviewer guide were used to generate qualitative information. Bivariate andrnmultivariate analyses were done. Odds ratio with 95% confidence interval was estimated to identifyrnpredictors of early sexual debut using multivariable logistic regression analysis. Qualitative datarnwere analyzed using thematic analysis.rnResult: Early sexual initiation (sex before the age of 18yrs) among youth in Addis Ababa was 42%.rnAmong youths who had history of sexual debut at early age thirty-seven percent of them didnâ€™t userncondom at first sex and 44% of male participant had sex with commercial sex workers in their liferntime. Multivariate analysis:-Being female AOR = 4.46(1.41, 14.15), younger age group AOR=rn3.20[1.50, 6.82], school attendance AOR=3.52(2.14, 5.79), reported pressure to have sexualrnintercourse AOR=2.18(1.13, 4.23), watching sex movies at early age AOR=7.27(3.65, 14.48) andrnusing alcohol AOR=2.48(1.09, 5.63) were identified as independent predictors of early sexualrninitiation. Regarding consequences 37% of pregnancies were before the age of 18years. In addition,rn47% of youths had history of STI in the past 12 month prior to survey.rnConclusions: This study indicates that a considerable proportion of youths engages in sexualrnactivity at an early age and continues to practice risky sexual behaviors. Peer influence played arnmajor role in youths sexual behaviors. Watching sex movies at younger age (15-19) and use ofrnalcohol were found to be independent predictor of early sexual initiation. In order to protect youthrnfrom early sexual debut, schools should focus on promoting peer educators and the way of peerrndiscussion. Strategies should be designed to control the use of alcohol and to restrict watching sexrnmovies at early age