Simile is the most basic element of rhetorical devices which metaphor and metonymy are making based on it. There are almost no poem which does not have a simile. By this way we can survey poet's skill rate and many stylistics changes. Simile is the most important images among different images of fantasy that Rudaki likes it. Essentially, rhetorical devices of Rudaki's poetry is based on simile, metaphor and metonymy… and have little place in his poems. His similes are most sense to sense (about eighty percent) and similes which are rational to rational are less attention (about three percent). Most of similes are morsel namely in most cases the elements of simile are mentioned. The elements of simile that are known in Persian poetry and morsel are: cho, chon, hamcho, hamchon, chonan, chenan ke, kerdar, bar kerdar, be kerdar, be mesl, rast and asa. According to the form in simile, absolute simile has the highest frequency after subtrahend and compound. The abundance of these structures would be one of this level's properties. Respectively, similes form of Rudaki's poetry implies to trait and state, color, motion and meaning. Because the elements of simile are related to familiarity to nature and its manifestations, it causes to making most images of objects and natural elements In this paper, the author outlined the statistical analysis of simile on parties, structure and form.