The purpose of this study was to analyze the patterns and the interrelationships for meeting guidelines of three health behaviors including physical activity(PA), sedentary behavior(SB), and dietary behavior(DB) for Korean adolescents using 2007 KYRBS(Korea Youth Risk Behavior Survey) data. A cross-sectional design was used to assess 73392 middle-high school students. PA(moderate physical activity${geqq}$5times/week, or vigorous ${geqq}$3times/week), SB(watching TV, computer, DVD, video, etc. < 3 hr/day), and DB(servings of fruits ${geqq}$1 times/day, or vegetables ${geqq}$ 3 times/day) were categorized into two levels (meeting guidelines or not). Chi-squared tests were conducted to compare the prevalence of students not meeting these three health behaviors between boys and girls, and logistic linear regression was used to determine the interrelationships of three health behaviors. Students meeting guidelines for PA, SB, and DB were 31.0%(boys 42.6%, girls 18.0%), 74.7%(boys 75.4%, girls 74.0%), and 38.5%(boys 38.6%, girls 38.4%), respectively. In addition, there were significant differences between both genders for PA and SB (PA; $x^2(1)$=35175.11, p<.0001, SB; $x^2(1)$=19.44, p<.0001). Only 10.9% of students met all three guidelines and 12.4% did not meet all three. Pattern that simultaneously did not meet PA and DB were high in both boys(27.1%) and girls(37.2%). Students who did not meet DB were at greater risk of not meeting PA(Boys; OR 1.49, 95% CI 1.43 to 1.55, Girls; OR 1.42, 95% CI 1.34 to 1.50), and not meeting SB(Boys; OR 1.41, 95% CI 1.34 to 1.48, Girls; OR 1.36, 95% CI 1.29 to 1.43) compared with students who met DB. The findings of this study supported further evidence for the need of a multiple behavior approach considering gender and interrelationships among three behaviors.