The purpose of this study is to research the description of the famous ceremonial book, "De ceremoniis" which was compiled in the 10th century by the Byzantine emperor Constantine VII Porphyrogennetos. It reveals an important roll of the religious processions in the middle Byzantine period. The ceremonies and the churches in Constantinople are divided in the two remarkable groups; 1.the old urbane basilicas (ex. Hagia Sophia) with the great religious feasts, supported by the conservativeness of the society. 2.the new palace-churches (ex. "Nea" the New Church) with the less important memorial feasts of the saints, created by the real political needs.