Since Halliday’ s functional grammar provides the possibility of studying texts as a complete consistent whole it proves quite efficient in conducting literary studies. This branch of modern grammar relies on three main metafunctions including ideational, interpersonal, and textual ones, and is concerned with inspection of texts as well as examining the role of language in representation of reality, interpersonal interactions, and meaning of texts. Ideational metafunction is further divided into six kinds of processes which include material, mental, relational, behavioral, verbal, and existential ones. In ancient epic works due to the fact that the composer made an effort to create an objective palpable image from a national heroic tale he employed material processes more than other process types, however in new epics considering the change of coordinates in human societies, the composer depending on the form he selects for his tale may use different processes in his work. Mehdi Akhavan Sales who is the most distinguished contemporary epic composer had made use of mental and verbal processes the most, in the eighth trial poem. The narrative form of the tale, presence of a naqqal in the tale, and then the presence of the poet as naqqal or the second narrator, the descriptive dominance of the structure of the tale, and also the connection of the tale with Rostam’ s seventh trial are the chief reasons for employing these kinds of processes in the eighth trial.