25 Members (excluding the associate or suspended members but including the countries represented on their behalf) [The rulers are not necessarily the representatives in the organisation. ] :
| | UNITED ARAB EMIRATES | (Abu Dhabi ar + Al Karama f) | | President Sheikh Zayed II bin Sultan Al Nahyan | | |
| | BENGLADESH | (Dacca a) | | President Abu Sadat Mohammad Sayem | | |
| | BAHRAIN | (Manamah) | | Emir Sheikh Isa II bin Salman Al Khalifah | | |
| | ALGERIA | (Algiers a + El Biar d + El Mouradia r) | | President Houari Boumedienne | | |
| | EGYPT | (Cairo a + Alexandria r) | | President Anwar El-Sadat | | |
| | GUINEA | (Conakry) | | President Ahmed Sekou Toure | | |
| | INDONESIA | (Jakarta a + Bogor r + Chipanas r + Yogyakarta r + Tampaksiring r) | | President Suharto | | |
| | JORDAN | (Amman) | | King Hussein I | | |
| | KUWAIT | (Kuwait City) | | Emir Sheikh Sabah III Al Salim Al Sabah | | |
| | LIBYA | (Tripoli a) | | Guide Muammar Gaddafi | | |
| | MOROCCO | (Rabat a) | | King Hassan II | | |
| | MAURITANIA | (Nouakchott) | | President Moktar Ould Daddah | | |
| | MALAYSIA | (Kuala Lumpur) | | Sultan Yahya Petra | | |
| | NIGER | (Niamey) | | President Seyni Kountche | | |
| | OMAN | (Muscat) | | Sultan Qaboos bin Said | | |
| | PAKISTAN | (Islamabad) | | President Fazal Elahi Chaudhry | | |
| | QATAR | (Doha) | | Emir Sheikh Khalifah bin Hamad Al Thani | | |
| | SAUDI ARABIA | (Riyadh) | | King Khalid | | |
| | SUDAN | (Khartoum) | | President Gaafar Muhammad Numairy | | |
| | SOMALIA | (Mogadishu) | | President Muhammad Siad Barre | | |
| | SYRIA | (Damascus) | | President Hafez Al-Assad | | |
| | TUNISIA | (Tunis) | | President Habib Bourguiba | | |
| | TURKEY | (Ankara a) | | President Fahri Koruturk | | |
| | SOUTH YEMEN | (Aden) | | President Salem Ali Rubayyi | | |
| | NORTH YEMEN | (Sanaa) | | President Ibrahim Muhammad al-Hamadi | | |