Background: This study aimed to demonstrate the importance to recognize subjective body image on their mental health on adolescents. Methods: We used the chi-square test and the multiple logistic regression model to analyze the data of the “Korean Youth Health Behavior Survey in 2018” (n=42,259) conducted by the Korea Centers for Disease Control and Prevention. Results: As a result of the analysis, suicide ideation increased when the subject body image is thin and fat. Especially, the suicide ideation who recognized the subjective body image as thin is higher (odds ratio [OR], 1.666; 95% confidence interval [CI], 1.050- 1.295), and who recognized the subjective body image as fat is higher (OR, 1.134; 95% CI, 1.032-1.245) than the group who recognized the subjective body image as normal. Conclusion: When preparing a health policy on adolescent suicide issues, we need to consider the association between subjective body image and suicide ideation.