The appropriation of Marxism by Soviet psychology was heterogeneous and characterized by different stages. In the Soviet context, official versions, such as Reflexology (Bechterev), Reactology (Kornilov) and finally Activity Theory (Leontiev), identified the Marxist character of psychology as being natural, behavioral and object-based. Other authors, such as Rubinstein, advanced the concept of activity as an alternative to the concept of behavior, emphasizing a dialectical principle of the unity between activity and consciousness. Holzkamp transcended the mechanical appropriation of Marxism, overcoming the social determinism and the passive character of individuals, which was mainly promoted by the Kornilov-Leontiev axis, including Vygotsky between 1927 and 1931. Paradoxically, Holzkamp integrated Leontiev’s concept of activity within his work. The reasons for this option will be discussed in depth in this presentation, as well as other differences between Holzkamp and Soviet psychology in their appropriation of Marxism.