Abstract: This paper sheds Light on the significance of the embassies and the byzantine correspondence during the second Abbasid age (247-656 H / 847 – 1258 AD ). The importance of recognizing the qualities of the ambassadors and their political and cultural potential land their role of diplomatic relation . The paper aims at identifying the historical roots of the Islamic embassies delegated to the byzantine state . The paper also aims at highlighting the significance and the role played by ambassadors in the two states . Besides، the paper tries to identify the types of correspondence and messages .the paper follows the descriptive analytic approach   . The paper achieved several finding the most important of these are the diplomatic decision is an essential pillar in the state’s foreign policy، the diplomatic work of the Muslim also proved to be of different styles and ways

Keywords: Messengers, office, safety, accreditation, decision.