Problem setting. One of the modern common directions for the development of the European Research Area is the introduction of a new approach to scientific research. The basis of this approach is the paradigm innovation, Open science, Open to the world. The full implementation of this paradigm within the European Research Area is possible only if the implementation of open science policy at the level of individual countries is ensured.The essence of open science policy is the provision of open access to research data, scientific publications and research infrastructures and the like.Open access to research infrastructures should be noted separately, as research infrastructures are one of the main means of obtaining scientific output. Accordingly, there is a need to analyze existing and develop new approaches to maximize access to research infrastructures with a view to their continued use in the process of public policymaking of open science in Ukraine.Recent research and publications analysis. Some foreign scientists (Foster I., Hey T., Trefethen A., and others) have researched open science and access to research infrastructures as part of it, but the focus of their research is placed on a particular variety of research infrastructures - on e-infrastructure, while the issue of open access also applies to the so-called classic research infrastructures. Ukrainian scientists researched the importance of digital information resources, including portals and registers, for the development of the state (Karpenko O. V., Vatkovskaya M. G., Kulak N. V., and others), but some focused research into the role of such resources in public policy on open science has not yet been conducted.The paper objective. The article aims to substantiate the need to create an open register of research infrastructures as one of the important conditions for implementing a public policy of open science, to demonstrate the benefits of using such a register in general and for Ukraine in particular, and to consider the example of a Romanian open register of research infrastructures.The paper main body. The article demonstrates the importance of creating an open registry of research infrastructures to ensure the implementation of public open science policy, as well as its importance for particular research infrastructures. The list of advantages that the state and the average user of R&D and technical services received in the conditions of creation and operation of such an open register are outlined. The importance of the visibility of research infrastructures to search users and partners for further collaborative research is demonstrated. The functioning and algorithm of user actions on the example of the Romanian open register of research infrastructures are considered.Conclusions of the research. The European Commission and other European institutions, which influence the formation of rules and the direct pursuit of research within the European Research Area, are currently implementing the paradigm innovation, Open science, Openness to the world. Open science policy, as a component of it, is divided into several areas, in particular, open access to research infrastructures. However, without ensuring the visibility of research infrastructures to the end-user, efforts spent to increase the openness of research infrastructures can be considered wasteful.Creating an open register of research infrastructures helps to systematize information on existing research infrastructures and the services they provide, to increase the visibility of research infrastructures for all stakeholders, and to facilitate the accounting, monitoring and evaluation of their status and activities, etc.Besides, the creation of such a registry and a platform that provides effective access to it facilitates easy and clear communication between providers and consumers of scientific and technical services, which is an important prerequisite for accelerating scientific and technological progress in general.The example of Romania illustrates a possible algorithm for the operation of such a registry and platform. A well-defined mechanism of work, limits of liability and user instructions for access and communication can serve as a benchmark for Ukraine when creating similar digital resources. Given the international development of ERRIS services, it is advisable to consider using them for Ukrainian research infrastructures.The areas of further research may be to study the process of creating open registers of research infrastructures in other countries of the European Research Area to use their experience in Ukraine. Also, research openings may include mechanisms for ensuring the openness of research infrastructures.