This work realize a Marxist analysis of the concept of animal liberation in Peter Singer and Gary Francione, showing their liberal convergence. The comparative study is part of the Marxist paradigm within the Critical Animal Studies (CAS) and practical philosophy. At first, the divergences and convergences between utilitarian welfare and deontic abolition, new welfarism and abolitionism are shown, emphasizing a common and fundamental preference for a post-speciesist liberal democratic society (i.e. a democratic capitalism). In a second moment, from a Marxist reading, two potentialities of the principle of equal consideration and the principle of non-reification are shown. In a third moment, the limitations of the anti-speciesist critique of the exploitation of animals by capitalist societies, the denaturation of their speciesism and the approach of a liberal reformist political topology are examined. At the end of the process, the five convergences found are recapitulated and weighed, as well as the two potentialities and limitations of the concepts, as contributions to new studies on criticism and interpretation of the authors and new approaches to the problem of animal liberation.