The XX International Conference on Chemical Thermodynamics in Russia (RCCT 2015) is organized to bring together scientists from all domains of Physical Chemistry in order to exchange their recent experience and achievements, to improve scientific cooperation. Traditionally the Conference is organized since 1961 in different Russian scientific centers (including former USSR member states during Soviet time): seven times in Moscow, three times in Saint Petersburg, twice in Tbilisi and once in such cities as Krasnoyarsk, Novosibirsk, Nizhni Novgorod,Ivanovo, Suzdal, Kazan, and Samara. Conference program includes plenary lectures, oral presentations, round tables and poster sessions.