The article analyzes, above all, the first stage of relations between the PC of Paraguay and the Communist International (Comintern), when the PCP suffered the internal crisis and change of leader as a consequence of the direct interference of the South American Secretariat of the Comintern. The text also contains an outline of contacts maintained by Moscow and the PCP throughout the 1930s. On the basis of the documents of the Comintern kept in Moscow, and some other archives, the authors recover a little-known history in the historiography of the Paraguayan left.