BACKGROUND: During the preschool years, children experience rapid development of inhibitory control (IC). This period is also crucial to foster the establishment of the foundations of physical fitness (PF) and motor competence (MC), which are essential for long-term health outcomes. This study aimed to investigate the predictive roles of PF and MC in IC in preschool children. METHOD: A total of 139 children (78 boys and 61 girls) participated in the study, with a mean age of 5.76 ± 0.30 years and a body mass index (BMI) of 16.15 ± 1.94 kg/m². Children performed the Go/No-Go test, Körperkoordinationstest für Kinder (KTK3+) test, static and dynamic balance tests, a pro-agility and countermovement jumping (CMJ) test. RESULTS: The findings showed that there was a positive association between MCT and accuracy number (AC) (go) (β = 0.079, 95%CI: 0.051-0.107), AC (no go) (β = 0.022, 95%CI: 0.003-0.041). However, between MCT and reaction time (RT), there was a negative relationship (β = [Formula: see text]0.497, 95%CI: [Formula: see text]0.988 - [Formula: see text]0.006). MCT scores showed a significant positive relationship with AC (go), with a beta coefficient of 0.309 (95% CI: 0.181, 0.436). This finding further underscores the robustness of this relationship. The PF indicator agility showed a negative relationship with AC (go) (β = -3.638 [-5.590, -1.687]) and static balance was negatively related to RT (β = -34.767, 95% CI [0.018, 0.165]). CONCLUSIONS: Overall, this study indicates that MC, rather than general PF, is strongly associated with the concurrent level of IC during the preschool period. These findings highlight the potential importance of promoting MC through targeted interventions that may support cognitive function in young children. Further longitudinal research is recommended to explore the causal relationships and long-term effects of these interventions. STUDY REGISTRATION: Research protocol number: 2022.214.11.15.