Objective : This study aimed to assess the applicability of the Yonsei Lifestyle Profile (YLP), initially developed for adults, for adolescents and verify its reliability and validity. Methods : This study evaluated the reliability and validity of the YLP among 436 middle and high school students in South Korea. The internal consistency of this scale was analyzed using Cronbach’s alpha and Spearman-Brown’s coefficient. Concurrent validity was assessed using Pearson’s correlation coefficient with the Korean Youth Physical Activity Questionnaire, the Korean version of the Children and Adolescents Participation Scale, and the Nutrition Quotient for Adolescents. Results : The overall internal consistency of the YLP items demonstrated high reliability, with a Cronbach’s α of .811 and Spearman-Brown’s coefficient of .779. Significant positive correlations were observed for physical activity (r=.555, p<.01), activity participation (r=.177, p<.01), and dietary habits (r =.633, p<.05), indicating consistent correlations with the related scales. Conclusion : This study analyzed the YLP targeting adolescents and confirmed its high reliability and significant validity in the areas of physical activity, activity participation, and dietary habits. These findings suggest that the YLP can be utilized as a reliable tool for evaluating healthy lifestyles among adolescents.