Medardo Griotto (born 16 February 1901 in Turin, 22 or 28 July 1943 in Plötzensee Prison) was an Italian militant communist activist and member of the Italian Communist Party. Trained as a engraver, Griotto became an expert forger, who became and important member in the espionage network run by Communist International (Comintern) intelligence agent Henry Robinson. Griotto was betrayed by Leopold Trepper, arrested and executed by guillotine at Plötzensee Prison.