["American Journal of Human Biology, Volume 38, Issue 8, August 2026. ", "\nABSTRACT\n\nBackground\nMotor competence (MC) has been proposed as an important correlate of physical and mental health during youth. However, evidence examining its associations with both health‐related physical fitness and mental health in Spanish adolescents remains limited.\n\n\nObjective\nTo examine the associations between objectively assessed MC and health‐related physical fitness and mental health in Spanish adolescents.\n\n\nMethods\nThis cross‐sectional study included 273 adolescents (46.9% girls; 12–17 years). MC was assessed using the Bruininks–Oseretsky Test of Motor Proficiency Short Form (BOT‐2 SF). Anthropometric measures, physical fitness, and mental health were assessed using validated protocols and questionnaires. Two‐level linear mixed‐effects and generalized estimating equation logistic regression models were adjusted for sex, biological maturation, socioeconomic status, and self‐reported physical activity.\n\n\nResults\nHigher MC was consistently associated with more favorable health‐related physical fitness outcomes (all p < 0.001) and with a greater likelihood of meeting established health‐related physical fitness criteria. MC was inversely associated with waist‐to‐height ratio (p = 0.028), whereas no consistent associations were observed with other anthropometric measures or mental health outcomes.\n\n\nConclusion\nHigher MC was consistently associated with health‐related physical fitness in Spanish adolescents, whereas associations with anthropometric measures and mental health were limited. Future adequately powered longitudinal and intervention studies are warranted to clarify the directionality of these relationships.\n\n"]