Indonesia joined the IsDB as a founding member in 1974. Its subscribed capital is ID 1,138 million (2.26% of IsDB total subscribed capital). It is also a member of all the IsDB Group Entities.

Indonesia is the largest archipelago-state in the world comprising 17,508 islands, about 6,000 of which are inhabited. It shares borders with Malaysia, Papua New Guinea and East Timur. It has a population of 262 million (2017) making it the world's 4th most populous country and the largest Muslim country by population. It is the world's 16th largest economy in terms of nominal GDP (US$1,015 billion in 2017); the world's 8th largest economy in terms of purchasing power parity; the largest OIC economy; the largest economy in Southeast Asia; and a member of the G-20. The country has around 300 ethnic groups speaking more than 600 languages. Bahasa Indonesia is the official language of the country.