Since the signing of the Paris Agreement, societal concern regarding climate change and sustainable development has grown exponentially. The construction of ESG (Environmental, Social, and Governance) frameworks and the disclosure of environmental accounting information have garnered significant attention. Constructing a financial ESG framework and refining its environmental accounting system holds paramount significance. This study employs a case study approach, using leading Chinese securities firm, CITIC Securities, as a focal point. It elucidates the complementary relationship between ESG frameworks and environmental accounting within financial institutions. Leveraging databases and publicly available information such as CITIC Securities' annual reports and corporate social responsibility report, the study systematically analyzes the development of CITIC Securities' ESG framework and the current status of environmental accounting information disclosure. Based on these findings, the study identifies issues in CITIC Securities' and other financial institutions' information disclosure practices, such as a tendency towards one-sided disclosure or the presence of "greenwashing" phenomena. Finally, the study proposes measures and recommendations in four key areas: standardization, enhanced disclosure, independent verification, and digitization empowerment.