Purpose: To study the health status and risk behavior in an adolescent population of Madrid, Spain.Methods: An anonymous self-administered questionnaire was completed by 2831 pupils aged 14-20 years from urban, suburban, and rural populations in the north of Madrid. A large number of questions were from the Minnesota Adolescent Health Survey questionnaire, which included sociodemographics, health status, drug use, sexual practices, suicidal thoughts, emotional problems, and injury risk. Student's t-test, analysis of variance, and Chi-square statistics are used for analyzing associations between the different variables.Results: A majority (80%) of students thought they are in good or very good health (better for males than females); 18.3% had had intercourse, the average age of the first intercourse was 15.4 years +/- 1.68 SD for males and 16.1 years +/- 1.46 SD for females. Most (73%) had used some kind of contraception. Eighty-five percent had tried alcohol, and regular use (frequently or every day) was as high as 24%. Males drank more than females (28% vs. 20%); 58.2% of the population drink only during weekends, the percentage increasing with age. Seventy percent of the sample had smoked at least once; 34.5% reported regular tobacco use and this increased with age. Males smoked less than females (27% vs. 42%); 3.2% smoked more than 20 cigarettes/day. The consumption of illegal drugs was very low (20% had tasted cannabis and use by males was higher). Cocaine, heroin, etc. were used by less than 5%.Conclusion: In general, our adolescents are in good health with most problems being preventable. Sexual activity was lower than in other European and American countries. The consumption of tobacco and alcohol started early and in general was high. Our study confirms the relationship among different health-compromising behaviors. There is a need to implement health promotion and preventive programs for adolescents.