Purpose: This study was done to explore the rates and methods of contraception among Korean adolescents from 2007 to 2009. Methods: The study was a descriptive study. The data were taken from a web-based survey on risk behavior of Korean youth that was conducted between 2007 and 2009 by the Korea Centers for Disease Control and Prevention. Results: Among adolescents, 4.7% in 2007, 4.6% in 2008, and 4.7% in 2009 reported having had sexual intercourse. In those who had sexual experiences, less than 30% reported consistent use of contraception, whereas more than 45% report no contraceptive use at all. A condom was the most frequently used contraceptive method and its use has increased continuously among contraceptive users. Some of the adolescents were, nevertheless, using unreliable methods such as withdrawal or the rhythm method. Conclusion: The results of this study indicate that most adolescents are not using contraception consistently and some were relying on unreliable contraceptive methods. Efforts to raise awareness about consistent and correct contraceptive use and the importance of dual protection are essential.