This paper aims to conduct in-depth research on the design and implementation of an accounting information management system based on the B/S architecture. Accounting firms play an indispensable role in corporate auditing, evaluating the legitimacy of internal control systems and promoting the steady development of enterprises towards standardization and legality. Against the backdrop of large-scale entry and increasingly fierce competition from foreign-funded enterprises, domestic accounting firms urgently need to improve their business and management levels, and the use of information technology has become an unavoidable trend. This system starts from the two core aspects of business management and human resource management. Through in-depth system requirement analysis, careful selection of development tools, and careful design of databases, it comprehensively optimizes key areas such as management mode, human resource allocation, and business processes, significantly improving the work efficiency and management level of the accounting firm. In the future, we will continue to improve our system to meet the constantly evolving industry demands and challenges. This study aims to provide practical experience and inspiration for the modernization transformation of accounting firms, and promote the industry to move towards a more standardized and efficient development direction.