<p>The effects of scaffolding—an instructional tool that offers guidance and support to students—on education have received a lot of attention. However, opinions differ on how scaffolding influences students’ problem-solving ability. In this study, meta-analysis method was used to analyse the overall and moderated effects of 32 experimental or quasi-experimental studies with a total of 55 effect sizes between 1976 and 2024. The study found that scaffolding could effectively promote students’ problem-solving ability (g = 0.776). The moderating analysis results demonstrated that fading mechanisms and discipline types are the real moderators, while scaffolding purpose, scaffolding source, problem types, region, grades, sample size, intervention duration, and measurement node are not real moderators. These findings provide important implications for the study of scaffolding in problem-solving.</p>