Abstract. Introduction. The considered predicative lexical units of the modal-mental sphere are the units of the active lexical stock. The study of the German-Slavic lexical parallels “können – to know” in a comparative historical perspective allows us to identify their inherent phonetic transitions, structural-linguistic changes and semantic transformations in the diachronic perspective. Purpose: to explore the German-Slavic lexical parallels in etymological, phonetic, structural-linguistic and lexical-semantic aspects. Materials and methods. The theoretical basis of the work was provided by the scientific postulates given in the studies, including lexicographical ones, of domestic and foreign linguists. In the course of the research work, the descriptive method and the method of component analysis, synchronic- comparative and semantic-nominative methods were used. Research results, discussion. The first written evidence of können in the German language field dates back to the 8th century. Aletic modality was not primary for the verb, and dates back only to the Middle Upper German period. The common Slavic *znati indicates a common Indo- European linguistic substrate for the two language groups. The presence of nomina agentis with similar semantic meaning in the described correlates is noted. The integral seme “intellectual ability” and the differential seme “physical ability” in the lexemes in question are noted in the course of the study. The analysis of the German-Slavic parallels “können – to know” is given using the phraseological data. Conclusion. The study of the German-Slavic parallels “können – to know” revealed both common and different characteristics for them in the aspect of their functionallinguistic and lexical-semantic features. The importance of studying German-Slavic parallels in the reconstruction of German lexical archetypes is highlighted.