This article presents a research study that aims to explore sustainable approaches for developing professional skills in vocational education students in Thailand. This is the second phase of the research, which utilizes a qualitative research methodology. The key informants in this study are administrators of vocational education institutions, teachers, and students currently enrolled in vocational education institutions in Thailand, totaling 36 participants. The research uses a purposive sampling method and snowball sampling method. Data collection methods include document analysis, in-depth structured interviews, and observation. The results of the interviews are analyzed, and the content analysis is summarized. The research process consists of 4 steps: 1) literature review, 2) data collection, 3) data analysis, and 4) verification and confirmation. The research findings highlight several key considerations, including: 1) factors influencing the development of professional skills among vocational education students, such as curriculum design, support and counseling, practical training in workplaces, interactive learning, problem-solving and analytical thinking skills development, practical learning, and supportive learning environments, 2) approaches for sustainable professional skill development involve employing the appropriate approaches for self-development. The steps include setting clear goals and plans, active learning and training, technology skill development, experiential learning, problem-solving skill development, participation in professional activities, self-reflection, and continuous self-improvement. These approaches aim to enhance the competencies of vocational education students, ensuring quality and efficiency as part of lifelong learning and sustainable development.