Abstract: Relevance translation theory is a model of the application of cognitive pragmatics in translation studies.The research results are not few of the theory applied to the interpretation of text, while the works of the study of the theory itself is quite limited.This paper makes an attempt to give an interpretation of the fundamental concepts of the theory from the perspective of practical philosophy by making a comparison and analysis of ternary dialogue communication, cognitive context, intentions, optimal relevance and the fidelity and validity with language conversation practice, life world, language about regulations and rules, practice of dynamics and communicative pragmatic equivalence respectively as to confirm the theory of practical philosophy.