Translation epistemology and translation practice theory are essential components of Marx and Engels’ philosophy of translation and Marxist philosophy. In advancing the cause of human emancipation and the international workers’ movement, they offered classic interpretations and undertook successful practice in Marxist theory of translation studies. Grounded in their original texts and adopting an interdisciplinary perspective encompassing philosophy, political science, and translation studies, this paper systematically establishes the four epistemological dimensions of their translational thought namely, the political, communicative, scientific, and artistic—and examines the corresponding four aspects of translation practice theory. Their revolutionary translation philosophy highlights the dialectical unity between the epistemology and practice of translation within the framework of Marxist philosophy.