This study sought to characterize sexual behaviour, contraceptive use and contributory upbringing factors among young people who had dropped out of school or college in a Nigerian setting. A community-based, cross-sectional sexual survey of 161 young people aged between 15 and 35 who had dropped out of school or college was performed in Ado-Ekiti, south-west Nigeria, in April 2015. One hundred and nineteen of the respondents (73.9%) had had sexual intercourse. Mean age at sexual debut was 19.08±3.5 years. Of those with sexual experience, 79 (66.4%) had their sexual debut with a previous boy/girlfriend and 33 (27.7%) had it in their current relationship. Three (2.5%) respondents had first sex with a stranger. About 90% were still having sexual intercourse within 12 months of the survey; more males had had sex than females (81.1% versus 67.8%). Around 80% of those with sexual exposure practised a form of contraception, mainly use of the male condom, but fewer than 25% were all-time contraceptive users. Coming from a single-parent family (p=0.04) or from a family of poor economic status (AOR: 7.41; 95% CI: 0.69-0.83) were found to be associated with sexual debut by the age of 19 and premarital sex, respectively, in these young people. Unprotected sexual intimacy was found to be high among young school/college drop-outs in this region of Nigeria. This group of young people need targeted reproductive health intervention as they represent a potent route for HIV transmission in the region.