With the transition to distance education during the coronavirus pandemic, one of the most talked about teaching approaches has been the flipped learning model (FLM). Conducting the discussions about FLM on a solid basis can only be achieved by finding an answer to what the effect of FLM has in different fields and different education levels. Based on this idea, in this study, it is aimed to evaluate the results of the studies examining the effect of FLM on the mathematics achievement of primary and secondary school students. In the meta-analysis study conducted in this direction, using the findings of 45 studies that meet the specified criteria, the effect level of FLM on students 'mathematics achievement compared to traditional teaching and also the effect level of FLM on students' mathematics achievement over a single group were determined. In the meta-analysis conducted in order to compare FLM with traditional teaching, it was concluded that FLM was moderately more effective (d = 0.51) in increasing students' mathematics achievement compared to traditional education. According to the meta-analysis results made to determine the effect of FLM over a single group, FLM has a high effect on mathematics achievement (d = 2.13). As a result of the analysis made according to the moderators of the study, the effect size of the FLM when compared to traditional teaching differs according to the type of publication and sample size and the effect size of the FLM over a single group differs only according to the sample size.