The prevalence of smokers in children and adolescents in Indonesia reaches 19.4%, the highest at the age of 15-18 years. Smoking behavior can cause pathological conditions in the oral cavity, including disorders of the soft tissue and hard tissue of the teeth. To determine the relationship between smoking behavior and oral hygiene in adolescents aged 15-18 years in Mulyasari Village, Tasikmalaya City. Analytical observational research with a cross sectional approach and carried out in Mulyasari Village, Tasikmalaya City, with 25 teenage boys aged 15-18 years as respondents, taking the sample using the slovin formula. The instrument used was a questionnaire and an OHI-S examination. The data analysis technique used the Spearman correlation test. Most of the smoking behavior in adolescents aged 15-18 years had moderate criteria as many as 11 people (44%), and the results of observations of dental and oral hygiene examinations (OHI-S) in adolescents aged 15-18 years were mostly in the moderate category. 12 people (48%). The results of the Spearman correlation statistical test obtained a probability value (p-value) = 0.030, and a correlation value of 0.435 indicating a positive correlation with moderate correlation strength (medium). There is a relationship between smoking behavior and oral hygiene in adolescents aged 15-18 years in Mulyasari Village, Tasikmalaya City.