<![CDATA[Background: Smoking behavior among adolescents remains a serious public health issue because it can increase the risk of various chronic diseases from an early age. The high prevalence of smoking among students at Gemeen 3 Junior High School, along with the rising cases of smoking-related diseases in the Gemeh area, indicates the need for research on the smoking behavior of junior high school adolescents. Purpose: To determine the description of the level of knowledge, attitudes, and smoking behavior among 8th and 9th-grade students. Method: This study uses a descriptive quantitative design with a cross-sectional study approach. This research was conducted in October–November 2025 at State Junior High School 3 Gemeh, Gemeh District, Talaud Islands Regency. The study sample consisted of 67 respondents selected using a total sampling technique, while data collection was conducted using a standardized questionnaire regarding knowledge, attitudes, and smoking behavior. Results: The study results indicate that most respondents have good knowledge and attitudes regarding the dangers of smoking, however, some students were still found to engage in smoking behavior. Smoking behavior is influenced by environmental factors such as peers, ease of obtaining cigarettes, and exposure to smoking habits around the respondents. Conclusion: Students generally have good knowledge and attitudes about the dangers of smoking, but smoking behavior is still observed in some respondents. Continuous promotive and preventive efforts are needed through health education, school environment supervision, and family involvement to prevent smoking behavior among adolescents. Keywords: Adolescents; Knowledge and Attitude; Smoking Behavior. ]]>
