This article is a case study of the blue finance mechanism (BFM) in China and makes use of evolutionary game theory and numerical simulation to show how the BFM plays a critical role in promoting the sustainable development of China’s marine economy, society, and environment. To ensure the perpetuation of the BFM, it is necessary for the Chinese government to attract private sector investment in the marine sector (PSIMS). By intervening in the BFM, the government can create a more favorable investment environment, which can then lead to greater private sector investment and contribute to the overall sustainability of the ocean. The goal of this article is to create an analytical model based on public finance and government management to examine the efficiency of Chinese governmental involvement in the BFM in order to boost the maritime industry by attracting private sector investment for funding the BFM. The results revealed the following: First, governmental involvement can have significant positive effects in promoting the sustainable development of the BFM in China. Second, the timeliness of governmental intervention in China can affect the private sector’s incentive to invest in the marine sector. Third, the Chinese government’s intervention in subsidizing costs can have significant impacts in engaging the private sectors to expand capital injection into marine investments. The minimization of potential risks of investment in the marine sector is critical to enhancing investor confidence and trust. The early intervention of the Chinese government is therefore crucial. Additionally, to further incentivize PSIMS, the Chinese government must make a concerted effort to increase subsidies and provide non-monetary rewards. This will help achieve sustainable development in the country’s economy, society, and environment.