The adolescence period is a very critical developmental period for personality, socializing and promotion of physical activity. In this regard, the aim of this study was to compare domain-specific physical activity efficacy level between adolescent boys and girls. A total of 219 girls (body weight: 57.50 ± 10.44 kg, height: 160.30 ± 7.40 cm, age 16.15 ± 0.96 years) and 145 high school boys (body weight: 63.45 ± 10.10 kg, height: 173.71 ± 5.49cm, age 16.20 ± 3.49) participated in this study. Physical activity efficacy level was evaluated by the Domain Specific Physical Activity Efficacy Questionnaire (DSPAEQ) which was adapted into Turkish by Saygin et al. (2017). Statistical analysis has shown DSPAEQ score differences between girls and boys (p<0.05). Scores for the school activity (p<0.05), transportation activity (p<0.05) and leisure activity (p<0.05) sub-dimensions were higher in boys than in girls. However, the household activity sub-dimension score was higher in girls than in boys (p<0.05). The results from this study indicated that adolescent girls should be encouraged towards more physical activity both at school and out of school. However, comprehensive studies with larger samples are needed for a better understanding of the participation of adolescents in physical activity.