This study examines how Project-Based Learning (PjBL) has been implemented to support the development of 4C competencies, critical thinking, creative thinking, communication, and collaboration, within vocational education contexts. Beyond identifying reported learning outcomes, this review contributes by synthesizing the instructional elements, implementation patterns, and supporting frameworks that characterize successful PjBL practices across recent studies. This study employed a PRISMA-based Systematic Literature Review of 19 Scopus-indexed articles published between 2021 and 2025. The review process consisted of article identification, screening, eligibility assessment, data extraction, and thematic synthesis based on predefined inclusion and exclusion criteria. The findings indicate that PjBL is consistently associated with the development of 4C competencies through the use of authentic projects, workplace-related learning tasks, and student-centered activities. Across the reviewed studies, several recurring elements were identified as important for effective implementation, including authentic problem-solving, collaboration and teamwork, student voice and choice, inquiry processes, reflection and feedback, public presentation of project outcomes, and technology-supported learning environments. The review also found that quantitative research designs were most frequently used to investigate 4C skill development. Furthermore, the framework proposed by Jang, Yusri, and Mustapha emerged as a useful reference for organizing PjBL implementation through structured project planning, execution, and evaluation stages. In conclusion, the reviewed literature suggests that PjBL represents a promising pedagogical approach for supporting 4C competency development in vocational education. The study provides a synthesized set of implementation elements and framework considerations that may inform future research and instructional design in vocational learning environments.