The present research aims to investigate the place of noun in Persian language based on cognitive approach by relying on the framework of Lanckager’ s cognitive grammar (2008). To achieve this goal, authors have selected 150 Persian simple nouns from Sokhan Dictionary (1382) accidentally. The method of the present research is descriptive-analytical and data collecting is based on library studies. After the study of collected data of research, authors concluded that in Persian language, the discussion on being countable or noncountable of noun doesn’ t make much sense and unlike cognitive approach mass nouns are the same as countable nouns, which receive plural – s morpheme and together with proper nouns, they constitute a different class of nouns. Also in Persian language as well as cognitive approach, pronouns can replace nouns.