The contribution presents the evolution of the basic functions of the stock market that have changed to the greatest extent under the influence of digitalization (the functions of pricing, ensuring liquidity and reducing information asymmetry). Particular attention is paid to the impact of such digital technologies as high-frequency and algorithmic trading, big data analysis on the functioning of the stock market. The research methodology is based on an interdisciplinary approach and includes system, comparative and content analysis. As a result, the key aspects of the influence of digitalization processes on the functions of the stock market, the transformation of the mechanisms for their implementation are presented. Recommendations are developed for adapting the institutional regulation of the stock market to the new challenges of digital transformation. Approaches to regulating digital assets, ensuring equal access of participants to information and managing the risks associated with the use of algorithmic trading are proposed. The results of the study can be used in the development of regulations for stock market participants, regulatory authorities and financial institutions in order to ensure the efficiency of the stock market.