The present study aims at investigating English lexicon polysemy within cognitive approach to study the way based on which Persian language learners learn English lexicon with the concepts used in cognitive linguistics such as, prototype, polysemy, categorization, etc. The nature of the methodology used in this qualitative research for studying the meanings of English lexicon is descriptive-analytic method. After the semantic analysis of English lexicon based on the model of Dirven & Verspoor (2004), it was found that the meanings of lexicon are classifiable based on theoretical procedures on cognitive semantics. The authors are trying to show the cognitive concepts in cognitive linguistics can be used for teaching English lexicon. The findings, generally, showed that the unconscious knowledge of learners in learning the cognitive structure of the meanings of lexicon has a meaningful relationship with learning. The results also revealed that the lexicon has a semantic network semantically, in which the notion of core or prototype is located in the center of the semantic network and the rest of the meanings can be examined as the peripheral meanings of a lexicon.
