Objective To assess prevalence and risk factors associated with drug abuse among public elementary, and high school students in the southern city of Florianopolis, Brazil. Methods A descriptive cross-sectional study was carried out using a standardized questionnaire created during the 4th National Survey on Drug Abuse. Four hundred and seventy-eight students were interviewed by trained college students. Of the interviewees, 43% aged 13-15 years and 32% aged 16-18 years and they had a higher socioeconomic status than the national average. Results Ever use prevalence for alcohol, marijuana, solvent drugs and amphetamines was 86.8%. 19.9%, 18.2% and 8.4%, respectively. Regular use 6 or more times per month) of alcohol, marijuana, solvent drugs and amphetamines was found in 24.2%, 4.9%, 2.5% and 2.3% of students, respectively, a higher percentage when compared to other southern states' capitals and the national average. Age, sex, social status and living with both parents were signiflicantly associated with drug abuse. Girls were twice as likely to consume weight loss drugs and stimulants, and almost three times more likely to use tranquilizers without medical prescription. Boys were almost twice as likely to use solvent drugs. Higher social students were twice as likely to consume alcohol than those of lower social status. Cigarette anti marijuana smoking, respectively, were 84% and 67% more likely among students whose parents were separated. Conclusions There is a high prevalence of drug use among elementany and high school students in Florianopolis.