Purpose: Our objective is to describe the moderating effect of the level of gross motor development on the relationship between physical activity (PA) level and visual perception/memory in girls. Methods: This is a quantitative cross-sectional study with a randomized sample of 85 girls (mean age 7.11±0.74) from Chile. The following models were tested: interaction between PA (light: Model 1; moderate-vigorous: Model 2; vigorous: Model 3; and total PA: Model 4) and motor development level associated with visual perception/memory. Variables that showed interaction were tested according to the Johnson-Newman. Results: The Model 2 explains 13% of visual perception/memory and the Model 4 explains 15%, indicating that the motor development level is a moderator of this relationship. Conclusions: Collectively, our results present evidence that girls with a high level of gross motor skills have a stronger relationship between total PA (and also only moderate-vigorous activity) and visual perception/memory.