The objectives of this study are to investigate the efficiency of state power use in governing the country towards a green economy and to examine proactive strategies to enhance the efficiency of state power use. This study employs a mixed-methods research approach, including quantitative research involving the construction of a model, SEM-LCM-VECM, to assess the above efficiency. Additionally, the findings from quantitative research are integrated into qualitative research to formulate proactive strategies for exercising state power to foster sustainable development. The findings indicate that the use of state power for the development of a green economy, in accordance with the 20-Year National Strategic Plan and various development strategies of Thailand, has proven to be inefficient. This inefficiency stems from continuous growth in the economic and social sectors, while the environmental sector has consistently deteriorated. The most significant contributing factor directly impacting the environment is the economic sector, followed by the social sector. Moreover, Thailand's adaptability towards sustainability has been notably slow and falls below the established standards. If the government continues to use state power and pursue policies in a manner similar to the past, it is likely to have severe adverse consequences for the environment. This is due to the fact that reactive measures, including civil measures, administrative measures, and criminal measures, cannot effectively facilitate the development of a green economy. Therefore, the guidelines for addressing and formulating proactive strategies are of paramount importance and highly necessary for achieving sustainability. Research findings suggest that the government must establish reactive measures alongside proactive measures in economic aspects. These measures include 1) taxation and revenue collection; 2) subsidies and tax incentives; 3) financial enforcement incentives; 4) deposit systems and refund mechanisms; and 5) ownership and market creation systems. The study also reveals that countries efficiently implementing these economic measures for sustainability include European nations and Asian countries such as South Korea and Japan. Consequently, Thailand should consider applying the research findings to appropriately and efficiently shape the use of state power before the nation causes further irreparable damage. It is imperative that these proactive measures are pursued diligently and continuously to promote green economy policies and ensure sustainability in both the present and future.