Background: Sexual relationship (SR) prevalence changes according the sociocultural context. Among adolescents, RS has negative outcome like non-expected pregnancy and sexually transmissible diseases. Objective: To establish the prevalence of SR in adolescent student from three official schools from Santa Marta, Colombia, and exploring some associated factors. Method: A transversal study was designed. Adolescent students, aged from thirteen to seventeen year-old, answered an anonymous and self report survey that it asked for sociocultural characteristics, and others health risk behaviors like alcohol drinking. Results: Fi ve hundred thirty two stude nts were included. Mean age was 14.7 years (SD 1.31); 56.2% was girls, and mean education was 9.1 years (SD 1.53) (53% middle school and 47% high school). SR prevalence was 27.8% (CI 95% 24.0-31.6). Logistic regression showed association between SR and being male (OR 10.53, CI 95% 6.25-17.54), older (OR 1.90, CI 95% 1.57-2.30), last month smoking (OR 2.27, CI 95% 1.38-3.73), and last month alcohol consum e (OR 2.05, CI 95% 1.01-4.81). Conclusions: One of each four adolescent student have had SR. Experimented sexual adolescents are more likely being males, older, and reported alcohol drinking and cigarette smoking.