Physical activity is widely recognised as an important component of children’s physical, psychological, and social well-being, which is closely associated with their overall quality of life. However, empirical evidence regarding this relationship among elementary school students in Indonesia remains limited. This study aimed to examine the association between physical activity and quality of life among elementary school students. A quantitative cross-sectional correlational design was employed, involving 159 students from a public elementary school. Physical activity was measured using the Physical Activity Questionnaire for Older Children (PAQ-C), while quality of life was assessed using the Elementary School Students’ Quality of Life (ESQoL) scale, comprising six domains. Data analysis included reliability testing, descriptive statistics, normality testing, Spearman correlation, partial correlation, and multiple regression analyses controlling for grade level and gender. Both instruments demonstrated acceptable internal consistency (PAQ-C α = 0.853; ESQoL α = 0.783). Results indicated a positive and statistically significant association between physical activity and overall quality of life (r = 0.254; p < 0.01), which remained significant after controlling for demographic variables. Regression analyses further revealed that physical activity was significantly associated with school functioning and peer relationships domains, but not with other domains. These findings indicate that physical activity is positively associated with specific aspects of elementary school students’ quality of life, although causal inferences cannot be drawn due to the cross-sectional design.