With the development of new technologies, such as communication and computer technology, we have entered the digital age. Blockchain technology and big data are widely used in all areas of life (medicine, manufacturing, education, construction, trade), and accounting and auditing are no exception. Modern management theories, largely based on the development of the industrial age, are rooted in the same as the function and methodology of internal auditing of enterprises. Internal audit, which is the third line of defense in enterprise risk management, is also in dire need of new theoretical and practical approaches to corporate governance and digital transformation. Paper analyzes digitalization challenges of internal audit from the perspective of changes caused by enterprise management digitalization, and analyzes the direction of digital transformation of internal audit from several aspects, such as informatization of audit objects and informatization of audit tools, in order to provide theoretical guidance for practice.