Abstract: There are common narrators between Sunni Muslims and Imamii Shiah so the way to evaluate them and the amount of the influence of religion factor on the evaluation of Sunni and Imami Shiah narrators in terms of Rejal science are of utmost importance. It seems that the issue of religion among Sunni initiatives seriously affects on the evaluations of narrators in terms of Rejal science and in the late Sunni scholars period is also of more importance. In Sunni sources, about one hundred and forty Shiah narrators are stated and a significant portion of them have been injured by the expressions of extremist, fanatic and heretic Shiah. Among Imamii Shiah there also exist 2 distinct periods in terms of religion influence on the evaluations of narrators in terms of rejqal science. In earlier periods, non-Imami narrators have been authenticated but in late periods, more stringency has been made in this area and some of narrators have been injured based on religion and their traditions have not been treated. Imami Shiah Rejalees are more stringent toward non Imami Shiah narrators than non Sunni narrators. The present study, through a comparative study, examines religion base between Sunni and Imami Shiah Rejals and attempts to evaluate its impact on each of these religions.