Abstract: Around Marx’s Economic and Philosophic Manuscripts of 1844, domestic scholarship has developed multiple representative interpretive approaches regarding its theoretical nature and historical positioning. However, most discussions have focused on evaluating the text’s overall intellectual stance, while relatively little attention has been paid to the structural articulation of its key internal categories. In the Economic and Philosophic Manuscripts of 1844, “labor” is not yet a fully formed socio-economic category grounded in concrete relations of production; rather, it functions as a transitional category spanning philosophical critique and critique of political economy. It is precisely this transitional character that allows “labor” to appear within the theoretical structure as a dual determination of ideal essence and real alienation, thereby constituting the internal driving force of the unfolding of alienated labor. The determinations of alienated labor and the genesis of private property are, in essence, a dialectical development of labor’s internal contradictions following a logical progression from object-relations to social relations. In this sense, the Economic and Philosophic Manuscripts of 1844 accomplish an initial transformation of dialectics from a speculative form into an analysis of real social relations through the category of “labor” while also revealing theoretical limitations that remain to be overcome. The theory of alienated labor can thus be understood as a methodologically significant moment in the development of Marx’s thought, whose internal tension directly contributed to the formation of historical materialism and the critique of political economy.