The main objective of the electric power industry is to provide for uninterrupted and reliable operation of power systems in order to meet the demand for electric power. The introduction of digital technologies in the wholesale electricity and capacity market is aimed at improving the efficiency, safety and continuity of its operation. The author highlights the features of legal support of digitalization in the wholesale electricity and capacity market, and proposes the possibility of expansion of the experimental legal regime to the wholesale electricity and capacity market. Information security issues are considered taking into account the fact that market participants may suffer not only financial and reputational losses from the implementation of security threats, but also damage to the life and health of people, the environment and the market infrastructure. The author concludes that it is necessary to develop means of legal protection of interests of owners and users of electronic software systems, as well as legal regulation of automated actions carried out in the wholesale electricity and capacity market. The research was carried out with the financial support of the RFBR within scientific project No. 20-311-90034.