This paper considers the organizational and legal support of the processes of digitalization of innovation in the financial and tax sectors. The main prerequisites were identified, and the role of financial and tax innovations in the development of the economy at the macro level was defined. Emphasis is on digital technologies as the main driving force of innovation in the financial and tax sector. The relationship between the concepts of "financial and tax innovations" and "financial engineering" has been established. The main directions of digitalization of the financial and tax sectors are identified. The digital technologies that have the greatest impact on financial and tax innovation are identified, namely: blockchain, Big Data, artificial intelligence, cloud technologies, the Internet of Things. The directions of legal regulation were substantiated and further steps to develop legal support for the digitalization of the financial sector were determined. To this end, the components of legal regulation, institutional regulation, and scientific and methodological regulation of digitalization of the financial sector are detailed. In contrast to numerous studies in the field of legal support and regulation of digitalization of the financial and tax sectors, it has been hypothesized and proved that the greatest effect is achieved with the harmonious interaction of institutional components. The system of management of financial and tax innovations in the context of digitalization has been improved. To this end, the stages of the transformation process of the financial and tax innovation management system in the context of digitalization were detailed and an algorithm for digitalization of the financial sector has been developed. The scope of practical application of the research results is the development of the financial and tax sector through the introduction of digital tools