In order to study and understand the meaning, concept, and the theme of an artistic and literary work, there have been applied, and tested, many various approaches. The focus on language, and context, which is a structural method, has based on formalism (structuralism) thoughts. In Iran, there are different tryings, to get a cohesive relation, between form and content, as linguistics and literary ways. These studies, are based on the Aristotale principles, the structuralist rhetorician, Jorjani, the ideas of Russian formalism, and the new methods in psychological and structural studies.Shahnameh, is the most outstanding, classical, and valuable Persian masterpiece. Shahnameh, with a theme of mythologic, heroic, and historical, in a fictional texture, full of conflicts, dialogues, monologues, narrative tellings with different tones, the conflicts in words and fields, full of glorious descriptions. Although the theme of life, passion and joy, are governing over the most of epics in shahnameh, but the theme of tragic death, also can be found there. Siavash, is one of the most tragic,not just in Iran, but in the world. These structural characteristics, has made the story, as one of the best tragic: The structural coherence, the harmony between form and theme, different conflicts, the causative relation between incidents, characteraization, the tone and p.o.v. of narrator in telling. Although, the language is performing its duty, in telling the story and the epic, it is fulfing its artistics function in the best form.This survey, is trying to find, and define the relation between the language and theme. Because of the unique nature of the text, the writer is emphasizing, on the mythological and historical cotext .The researcher believes that, the whole psychological aspects of the charactors, can be manifested through form (language) and the p. o.v., and the tone of narrator. This relation can be defined through description of different layers of language: phonology, morphology, syntax, semantics, and pragmatics.