Sustainable development audits require reliable, transparent, and accountable systems to verify both financial and non-financial data. Traditional auditing methods face challenges in handling large datasets, ensuring ESG metric accuracy, and providing continuous verification. Blockchain technology, with its decentralized and immutable ledger, offers promising solutions to these challenges. This study investigates the integration of blockchain into ESG and financial auditing, evaluates case studies from leading firms, and proposes a novel framework for holistic auditing. Findings indicate that blockchain enhances audit reliability, improves transparency, and enables real-time verification while reducing manual errors and potential fraud. The study emphasizes that blockchain is a complementary tool requiring auditor expertise, regulatory alignment, and standardized ESG metrics to achieve sustainable development accountability.