The purpose of this project is to study the roles and impact of science and technology parks in the entrepreneurial ecosystem. The project consists of three research papers including one conceptual paper and two empirical studies. The empirical studies are based on 31 semi- structured interviews with a wide range of entrepreneurial ecosystem actors and institutions. Each interview lasted between 58 and 173 minutes, for a total of 3,264 minutes, or an average of 105 minutes per session. The first paper addresses the gap in the entrepreneurial ecosystem literature that commonly overlooks the science and technology parks. Both entrepreneurial ecosystem and science and technology park literature were explored. This study highlights the conceptual roles of science and technology parks in the entrepreneurial ecosystem. The first study also provided the theoretical foundation for the later studies in this project. The second paper investigates a case study of Northern Science Park and the entrepreneurial ecosystem in Chiang Mai, Thailand. This case study provides not only the interrelationship between the two but also insights into the context of developing entrepreneurial ecosystems which is another gap in the literature. This study demonstrates the case that the science and technology park can play a leadership role in the ecosystem and has a significant influence on the evolution of a developing entrepreneurial ecosystem. The findings also reveal the importance of the entrepreneurial culture in the entrepreneurial ecosystem evolution. The third paper re-examines the dataset used in the second paper and focuses on how the science and technology park influences the entrepreneurial culture in the ecosystem. We revisit the entrepreneurial ecosystem literature to unpack the dimensions of entrepreneurial culture. Based on the previous work, support mechanisms of science and technology parks are identified. As a result, the model of entrepreneurial culture development is constructed. Overall, this research brings attention to the importance of the science and technology park, as a leader, in a developing entrepreneurial ecosystem. Moreover, this research highlights the importance of entrepreneurial culture in the entrepreneurial ecosystem evolution. This research provides policy implications by offering a theoretical framework to develop entrepreneurial ecosystem elements, particularly entrepreneurial culture.