Objective: To study the impact of active video games on Body Mass Index (BMI) in children and adolescents. Design and Methods: A systematic review and meta-analysis. Data were pooled in meta-analysis using the method of random effects or fixed effects, as appropriate, after examination of statistical heterogeneity. Data sources and eligibility criteria for selecting studies. A comprehensive literature research was conducted in Medline (PubMed), ISI web of Knowledge, and SCOPUS up to April 2018, in relation to clinical trials (both controlled and non-controlled) in children and adolescents, whose intervention was based on active video games. Results: The overall intragroup effect of the intervention based on active video games was in favor of the intervention, reaching statistical significance using the fixed effects model: (standardized mean difference (SMD) = −0.138; 95% CI (−0.237 to −0.038), p = 0.007 and was of borderline statistical significance in the random effects model: SMD= −0.191; 95% CI (−0.386 to 0.003), p = 0.053. The individual results of the determinations of the 15 included studies for this analysis showed a high heterogeneity among them (I 2 = 82.91%). When the intervention was applied to children and adolescents with greater than or equal to 85 (overweight or obese) BMI percentile showed a greater effect in favor of the active video games: SMD= −0.483, p = 0.012. The overall intra-group effect in the control group was close to zero (SMD = 0.087). With respect to the non-standardized mean difference (MD) between groups, it was also in favor of active video games for both BMI (Kg/m 2 ): DM = −0.317, 95% CI (−0.442 to −0.193), p = < 0.001 and BMI z-score: DM = −0.077, 95% CI (−0.139 to −0.016), p = 0.013. Conclusions: Our meta-analysis show a statistically significant effect in favor of using active video games on BMI in children and adolescents. The clinical relevance of this positive effect must be evaluated.has undergone a radical change with the arrival of a new generation of video games, active video games, which involve physical activity since they allow players to interact physically, through their body movements (arms, legs, or the whole body), with the virtual reality that appears on screen through different devices.Individual primary studies and subsequent meta-analyses have focused on the effects of active video games on the promotion of physical activity [3][4][5][6][7][8], energy expenditure , oxygen volume consumption [9,12,15,16,[27][28][29], and heart rate [9,14,15,17,18,[27][28][29][30][31][32]. These studies have shown an increase in heart rate and an increase in oxygen consumption. This energy consumption is statistically significantly higher compared to non-active video games and sedentary activities, despite the variability of the types of active video games, as well as the time spent playing them [5,7,19,[22][23][24][25][26]33].Regarding the effect of active video games on body mass index (BMI), various primary studies [21,31,[33][34][35][36][37][38][39][40][41] have analyzed...