The article focuses on political thinking in the 18th century Russia, which preceded the 19th and 20th century Russian liberalism. It is divided into two sections. The first sections focuses on certain difficulties connected with clarification of the term Russian liberalism (or more precisely liberalism in Russia) and the course of its existing research, i.e. the heterogeneous periodicity of Russian liberalism, the problematic specification of the term 'liberal' in the Russian milieu and the fluctuation of liberalism in Russia from positive to pejorative nuances. The second section pursues viewpoints of political thinkers and the development of public political life in the 18th century Russia, which was followed by Russian liberalism in the 19th and 20th century. The author pays attention to political ideas and standpoints of I. T. Pososhkov, D. M. Golicyn and V. N. Tatishchev and their attempts to weaken the tsarist power in 1730. He analyses the rise and advance of public movement and West European political thinkers' influence on the Russian political activity in the second half of the 18th century. Next, he analyses constitutionals projects of N. I. Panin, P. I. Panin and D. I. Fonvizin and ideas of S. J. Desnickij and A. N. Radishchev.