Purpose: The purpose of this study is to identify health risk behaviors in adolescents according to grade in school and to of for basic data to develop a health promotion for adolescents. Methods: A descriptive survey design was used and the SPSS 12.0 program was used for the data analysis, which included Chi-square test and Spearman correlation coefficients. The instrument for this study was based on the 1999 Youth Risk Behavior Surveillance System developed by the Centers for Disease Control and Prevention. Results: The results indicate that adolescent have an average of 2 risk behaviors out of 10 health risk behaviors categories. There are various types of risk behaviors, which art: different for each grade, such as physical fights, using alcohol, using heroin, weight control, and the lack of AIDS education. Physical fights, and the lack of AIDS education are common in the 9th grade, using alcohol, heroin, and weight control are common in the 11th grade. Physical fights were correlated with using cigarettes and sexual intercourses. Using alcohol was correlated with using cigarettes, heroin, sexual intercourses and weight controls. Using heroin was correlated with sexual intercourse and weight control. Conclusion: For the promotion of health in adolescents, different approaches to health education and prevention of health risk are needed for each grade because the health risk behaviors differ between grades.