<p>Motor competence is the individual's ability to execute various motor tasks skillfully, and perceived motor competence is the individual's belief in their competence in executing motor tasks. In the present study, the effect of a game-based intervention course on motor developmental quotient (and the subscales of locomotion and object control, AMC) and motor fitness (balance, reaction time and dexterity) in 8-year-old boys with high and low perceived motor competence (PMC) has been studied. Children with similar relative age and maturity age were categorised into two groups of high and low PMC based on the level of PMC. There were 15 people in each group. Developmental quotient (TGMD-2), perceived motor competence (Perceived Motor Competence Questionnaire in Childhood) and motor fitness factors were evaluated in two phases pre-test and post-test. The intervention consisted of 8&#xa0;weeks (two sessions per week) of gross and fine perceptual-motor games. The results showed that regardless of the level of PMC, children's performance developed significantly from pre-test to post-test in developmental quotient (and its subscales) and motor fitness factors. However, the effect size for the subscale of object control (rather than locomotion) was significantly greater (3.557 compared with 1.926). The results also indicated that children with high PMC exhibited significantly superior performance in all variables in the post-test compared to those with low PMC and the effect size of this difference for the locomotion skills subscale was considerably greater than that of object control skills (0.49 compared with 0.153). The findings of this study demonstrate that children with higher PMC have derived greater benefits from game-based interventions in the enhancement of AMC and the development of motor fitness factors. Therefore, it is imperative to consider the level of PMC before designing and implementing motor interventions.</p>