The article deals with the interpretation of Kant's theory of knowledge by Matteo Liberatore, a major representative of Neo-Scholastics in the middle of the 19^th century, in his treatise Della conoscenza intellettuale (1858). It is shown that his study of to Kant was conditioned by a number of tasks that were solved by Neo-Scholastics, i. e. (1) apologetic: overcoming Kant's criticism of theological argumentation; (2) critical: refuting the concurrent doctrines like Ontologism, Hermesianism, etc.; (3) conceptual: actualising scholastic philosophy in the context of the issues of Modern Time. A range of responses given by Liberatore's predecessors (G. Sanseverino, J. Balmes, J. Kleutgen) could not adequately present and effectively substantiate the Thomist theory of knowledge. Liberatore solved that problem on the basis of a consistent reconstruction of Aquinas' epistemology as part of the questions posed by the theories of knowledge in Modern Time. Taking into account the break in continuity between scholasticism and Modern European philosophy (for which Descartes is responsible), Liberatore notes that the subject content of both types of concepts is the same, although the method of determining the sources of knowledge differs. In particular, Liberatore denies the need to assume the original givenness of a certain content (innate ideas) or forms of constituting objects (a priori forms) that mediate the relationship of subject and the objective world. On the contrary, Liberatore assumes only the actual capacity of knowledge as a substantial quality of the rational soul, but it is devoid of content independent of the known reality (tabula rasa); it is formed due to a cognitive mechanism of abstractions and mediations (which Liberatore, like Aquinas and other scholastics, describes as intellectus agens et patiens), driven by affections on the part of objects. According to Liberatore, it is a mistake to give this mechanism its own place and a special non-objective content that becomes the focus of knowledge and obscures reality. However, this criticism of Kantianism did not mean that certain aspects of this theory could not be integrated as counter-arguments into Neo-Scholastic epistemology. Liberatore laid the ground for further research and interpretation of Kant's philosophy by Catholic intellectuals.