In terms of critical skills for academic achievement, the literature has revealed that the development of executive functions (EF) plays a key role. Although numerous researchers have aimed to improve EF through computerized cognitive training interventions, the evidence of the effect derived from these interventions remains ambiguous. The purpose of this study is to investigate the effects of a computerized game-based training program on EF and its impact on academic performance in 713 Spanish Primary School students (M = 10.2 years old, 51.3% girls). The EF training was carried out in 8 weeks, 3 sessions of 15-20 minutes each week, measuring students' EF and obtaining information on academic performance. The results showed an improvement within the training group in the questionnaires exploring inhibition and working memory, as well as in academic performance, compared to the control group. In contrast, no significant intergroup differences were observed in the inhibition tasks.