Promoting physical activity (PA) and eliminating health disparities among underserved minority children is a public health priority. The main purpose of this study was to examine the relationship of actual motor competence (a set of object control skills) and perceived motor competence with PA participation and health-related quality of life (HRQoL) among underserved Hispanic children who were born in the U.S. Guided by Stodden et al.'s conceptual model, we tested the direct and indirect effects (mediational model) of actual motor competence on health-related outcomes (PA and HRQoL) through perceived motor competence. Participants were 215 underserved Hispanic children (Mage = 10.55 years, SD = 0.53 [age range 10-12]; 51.6% boys), recruited from four elementary schools in the southwestern U.S., who completed validated questionnaires assessing their perceived motor competence, PA, and HRQoL. Their actual motor skills were assessed using PE MetricsTM. After examining the associations among the variables, we tested the hypothesized model using structural equation modeling (SEM; AMOS 25). The hypothesized model indicated a good fit (χ²/df = 38.427/24 = 1.60 < 5; non-normed fit index (NFI) = 0.93; comparative fit index (CFI) = 0.968; root mean square error of approximation (RMSEA) = 0.053 [0.016, 0.083]). The effect of actual motor competence on PA and HRQoL was fully mediated by perceived motor competence. The findings demonstrated the mediating role of perceived motor competence between actual motor competence and health-related outcomes (PA and HRQoL) among underserved Hispanic children. The results highlight that actual motor competence significantly predicted underserved Hispanic children' perceived motor competence, which in turn positively predicted their PA and HRQoL. These findings have significant practical implications for future intervention strategies of randomized clinical trials in schools aimed at promoting PA and HRQoL and eliminating health disparities among underserved Hispanic children.