The paper covers Ernesto Guevara’s views on managing the economy of Cuba which he expressed in the economic debate in the first half of 1960s. Participating in this discussion as a proponent of the budgetary finance system Guevara opposed advocates of the autofinancing system. During the debate he appealed to Marxist theory relying on original works of Marx, Engels and Lenin. From Guevara’s perspective, constructing socialism meant a transition to a qualitatively new system of categories among which centralized planning was the crucial one. Thus, this new system was utterly different from the one which was revealed by Marx in Das Kapital when the German scientists focused on capitalist mode of production. On the contrary, Guevara’s opponents highlighted that socialist construction could and should count on categories which functioned on the capitalist phase in order to promote efficiency. Being the Minister of Industries, Guevara brought his theory into practice at the production units that belonged to his Ministry. The author investigates several fundamental articles written by Guevara during the polemics, other sources the show Guevara’s vision of socialism and works of theoreticians whose ideas were used by the debaters. The paper also introduces archival materials (Russian State Archive of the Economy) that reveal some peculiarities of Cuban planning system formation.