One of the essential problems in the relationship between Catholic-Orthodox churches is the difference in the interpretation of the current forms of the primacy in the Church of the Bishop of Rome. Contemporary studies on the essence and on the method of accom-plishing this service on behalf of the universal Church’s unity assumed new dynamics after the publication of the ecumenical encyclical letter of John Paul II – Ut unum sint. The Pope addressed and requested the pastors and theologians to establish with him a “patient and fraternal dialogue” (see US 95-96), for both parties to strive to achieve “the forms in which this ministry may accomplish a service of love recognized by all concerned” (US 95). The contemporary Orthodox theologians, based on the results of historical studies, are con-vinced that the idea of the Roman primacy has been always presented in the theological awareness of the Christian East. The Eastern Churches do not negate the primacy of the Pope, as the Bishop of Rome, and as the first bishop of the whole Church. Recognizing the primacy of the Holy See as an incontestable historical fact, the Orthodox theologians see the crucial problem in the determination of its nature. They do not accept the primacy in the juridical sense.