Background and aims: The present study aimed to synthesize existing quantitative evidence on the relationship between problematic smartphone use (PSU) and academic achievement with a focus on quantifying its magnitude and examining its potential moderators. Methods: Eligible studies were searched for up to February 10, 2023 in six different databases (i.e., MEDLINE, Current Contents Connect, PsycINFO, Web of Science, SciELO, and Dissertations& Theses Global). Studies were considered eligible if they provided information derived from self-report instruments that allowed statistical calculation of the relationship between PSU and academic achievement. Pooled effect sizes (r) were computed using a random-effects model. Meta-regressions were conducted to test the influence of study-level moderators on the relationship of interest. Influence analyses and a three-parameter selection model (3PSM) were conducted to examine the robustness of the results and publication bias, respectively. Results: A total of 33 effect sizes from 29 studies (n 5 48,490) were retrieved. Results showed a small effect size (r 5
0.110), which tended to be larger in samples consisting of students from elementary and middle schools. Discussion and Conclusions: Findings from the present study contribute to the understanding of a potential determinant of decreased academic achievement by providing evidence that PSU may be one of them.  Kulcsszavak: human-computer interface, media in education, problematic smartphone use; smartphone dependence, smartphone addiction