The importance of in depth analysis of previous studies on the impact of project-based learning on student learning outcomes over the past ten years to obtain a clearer picture of learning abilities that can be applied to science learning. This study set out to ascertain how project-based learning models affected the learning results of the students. The effect size (ES) studied is the result of several studies that have been carried out. This research uses meta-analysis, namely reviewing similar research, which is summarized from various research results quantitatively by looking for effect size (ES) values. The study journals used were international journals indexed by Scopus in the last 10 years, totaling 10 journals. Data obtained from the research instrument was analyzed using the effect size formula. The average effect size value obtained was 0,78 which is in the medium category. The study's findings support the notion that implementing the project-based learning (PjBL) paradigm to teach science can enhance students' learning outcomes.