Improving scientific literacy is crucial for early childhood development, yet limited studies necessitate a thorough analysis to identify effective solutions. This study aims to analyze the implementation of project-based learning in early childhood education to improve scientific literacy. The study followed the identification, screening, eligibility assessment, and inclusion stages using a systematic literature review based on the PRISMA framework. Sources were accessed from databases such as Google Scholar, ERIC, Springer, JSTOR, Dimensions, and ScienceDirect, totalling 2085 articles. After screening articles published between 2014 and 2024, written in English, and relevant to the topic, 55 articles were selected for further analysis. The findings categorize approaches, trends, subjects, effects, and learning media used in adopting project-based learning to develop scientific literacy in early childhood. Two main approaches were identified: 1) narrative and dialogue and 2) project-based learning. Project-based learning is widely applied in 16 countries in Asia, America, Australia, and Europe. The review indicates that project-based learning improves early childhood scientific literacy in physics, biology, astronomy, and technology through learning media such as experimental tools, toys, robots, AR, VR, and AI. Therefore, implementing project-based learning supported by innovative learning media is an effective solution for improving scientific literacy in early childhood.