Imamiyyah and Ziydiyah's political and religious leadership, as two influential Shiite sects, is apparent. Hence, it is necessary to find out from the studies of the two leading Shiite sects, especially the Imamiyyah's intellectual history, to the points of divergence in their theology and hadith exchanges. This article seeks to show that in what ways these two important Shiite sects, had their intellectual relationship in the short occultation (ghiybah al-sughra) until the end of the sixth century. Who were working in this field? Relations between the two sects in these centuries have been driven by a series of core practices, but, because of some disagreements in religious principles, they have also been pursuing their distinction from each other. In order to answer to the questions and proving the hypotheses, the intellectual relationships between Imamiyyah and Ziydiyah in Iran, especially Rey, are examined, using historical methods and a descriptive-analytic method based on the primitive sources.