muhammad ibn muhammad ibn numan, known as "shaykh mufid," one of the great imamiye theologians and jurists in the fourth and early fifth century , had comprehensive mastery of both rational and traditional topics and exerted his influence upon both his contemporary and future scholors. he is considered to be one of the top imamiye scholars who spent his lifetime teaching, learning and authoring books on various scientific fields ranging from theology, jurisprudence, principles of jurisprudence to history, quranic sciences . theological and legal debates and discussions with scholars of other religions increased the prominence of this prolific character. despite writing at least four books on the subject of quranic sciences -not available today – shaykh mufid did not write any independant exegetical book. but by using the available exegetical books and his exegetical viewpoints, abundant amidst his other books, can be found some of his exegetical viewpoints. this thesis, based on shaykh mufid exegetical viewpoints, is trying to codify his foundations of quranology. the study of shaykh mufid’s exegetical topics, organized on the basis of rational- theoretical and traditional discussion, and based on multiple sources, shows that the understandability of the quran, the validity of its appearance, regarding the authenticity for masoomin sayings, and a belief in the hidden foundation for the holy qurans appearace are the most important premise of his argument. also studying shaykh mufids exegetical heritage determines that traditional interpretation, theological interpretation, the interpretation of the quran by the quran and literal interpretation are the most important exegetical methods adopted by him. some shaykh mufids foundations of quranology like the rejection of the revelation of holy quran all at once in the ghadr night, quran’s miracle in the sarfeh, the creation of the divine word, and his tendency to the "preservation of the holy quran from distortion" theory are studied in this thesis. keywords: shaikh mufid, exegetical method, traditional interpretation, theological interpretation, foundations of quranology. ش