In the era of big data, the financial industry is undergoing profound changes. By integrating multiple data sources such as transaction records, customer interactions, market trends, and regulatory requirements, big data technology has significantly improved the decision-making efficiency, customer insight, and risk management capabilities of financial institutions. The financial industry has become a pioneer in the application of big data technology, which is widely used in scenarios such as fraud detection, risk management, customer service optimization, and smart transactions. However, financial data security management also faces many challenges, including data breaches, privacy protection, compliance requirements, the complexity of emerging technologies, and the balance between data access and security. This article explores the major challenges of financial data security management, coping strategies, and the evolution of the regulatory environment, and it looks ahead to future trends, highlighting the important role of artificial intelligence and machine learning in financial data security.