This study examined adolescent girls’ breast anthropometry and perceptions of bra design, taking into account their specific breast shapes and needs. Twenty-three adolescent girls aged 10 to 14 were invited to participate in the survey to understand their knowledge level of bra-related issues, and 7 adolescent girls with bra sizes of 30AA to 32A were invited to wear trials. 3D scanning and questionnaires were conducted to obtain seven breast measurements and understand their preferences for bra design. The findings highlight the need for sports bras designed specifically for adolescents.