Abstract：Purpose: Sports are typically male dominated, this need to explain why sports spaces and facilities for women tend to be limited. This study explores the differences in sport participation, sport enjoyment and self-perception among boys and girls. Methods: The study population is composed of 10(superscript th) and 11(superscript th) grade students from two Hualien senior high schools. The survey was conducted using the James and Embrey (2001) survey instrument. Data were collected between December 2003 and January 2004 by obtaining 589 usable questionnaires from 262 boys and 327 girls. Results: Analytical results demonstrate that the ratios of boys and girls who actively participated in sport were 84% and 73%, respectively. The spending time over 30 minutes each time in sport was 80% for boys and 47% for girls, and the proportion of enjoying sport was 87% and 63% respectively. Additionally, twenty-three percent of girls never played sports outside the schools. Active boys showed positive athletic competence, physical appearance and self-worth perceptions. However, although active girls showed positive athletic competence perception, they had negative physical appearance and self-worth perceptions. Both inactive boys and girls showed negative athletic competence, physical appearance and self-worth perceptions. Conclusions: Based on the results, three conclusions were drawn. First, girls enjoyed sport less than boys. Second, girls expressed lower self-perceptions than boys. Finally, correlations were noted between sport participation (the degree of activeness and enjoyment) and self-perception (athletic competence, physical appearance and self-worth). From this study recommendations are made for practice and future research. (Full text)