Educational communities have expanded 3D printing in education, emphasizing the educational value of "creation" to develop the competencies required in the future. This study was conducted for the purpose of identifying the effect size by synthesizing prior studies on the effect of 3D printing in education. To achieve the goal, 26 research papers on 3D printing in education conducted in South Korea from 2014 to 2021 were selected and meta-analysis was performed. The results of meta-analysis are as follows. First, the overall effect size of 3D printing in education was 0.759, which was found to be a medium effect size. Second, the effect sizes for each categorical variable are as follows: both the affective domain and the cognitive domain showed medium effect sizes for the learning effects. Middle school showed a large effect size, and elementary school and high school had a medium effect size. Gifted students had a large effect size, and general students had a medium effect size. In terms of the concentrated subjects, mathematics showed a large effect size and science and technology showed a medium effect size. Single subject showed a large effect size and convergence education had a medium effect size. Both offline classes and blended classes showed increased effect sizes. Both the team activity and the individual activity showed a median effect size. The out-of-school program showed a large effect size, and the school program showed a medium effect size. 3D pens showed a large effect size, and 3D printers showed medium effect size. In terms of the modeling type, unstructured modeling showed a large effect size, as did semi-structured modeling, while semi-structured modeling showed a medium effect size. This study has implications for instructional design that can increase the effect of 3D printing in education.