Objectives : This study aims to improve health and the quality of life of teenagers by identifying an association between the periodontal status and oral health behaviors of Korean teenagers using 2010 Korean National Oral Health Survey data. Methods : Subjects were teenagers aged from 12 to 15 in Korean National Oral Health Survey (KNOHS). The questionnaire consisted of periodontal status, general characteristics, periodontal related factors, and oral health related behaviors. Results : Gingival bleeding was found in 56.9% of teenagers because unhealthy periodontal status and tartars were found. Those who were 15 years old had unhealthier periodontal status than those who aged 12 years old. Those who lived in rural areas tended to have worse periodontal status than those who lived in the big cities. Access to dental floss, mouth rinsing solution and regular dental checkup tended to make the healthier periodontal status. Smokers had the worse periodontal status than the nonsmokers. Conclusions : The oral health care in the teenagers aged from 12 to 15 is very important because the permanent dentition is completed in this stage. It is necessary to lay emphasis on the oral health improvement and dental caries prevention program to the teenagers.