ENThe article describes the process of the establishment and implementation of the new modern public science policy in postsoviet countries. The examples of Latvia and Lithuania demonstate the application of the open science paradigm at the state level. The legislative prerequisites for the establishment and implementation of the public open science policy in Latvia and Lithuania are considered. The role of individual higher education institutions in the implementation of the principles of openness in carrying out research activities is noted. The link between the existing open science normative documents in Latvia and Lithuania with the existing imperative and advisory documents of the European Union is demonstrated. The role of e-infrastructures, in particular repositories of scientific data and academic texts, in the implementation of open science policy at the state and institutional levels is shown.