ECOSAI is the Economic Cooperation Organisation Supreme Audit Institutions, currently comprises Supreme Audit Institutions (SAIs) of  Afghanistan, Azerbaijan, Iran, Kazakhstan, Kyrgyzstan, Pakistan, Tajikistan, Turkmenistan, Turkey and Uzbekistan. The SAI of the Turkish Republic of Northern Cyprus is allowed to participate in the activities of ECOSAI without prejudice to the respective positions of the member states and the on-going efforts for a final settlement of the question of Cyprus in accordance with relevant United Nations Security Council's resolutions.

ECOSAI was established in 1994 following a meeting of heads of the SAIs of Republic of Afghanistan Republic of Azerbaijan, Islamic Republic of Pakistan, Republic of Tajikistan and Republic of Turkey in Bhurban, Pakistan during 17-19 April 1994.

Article 2 of ECOSAI Charter defines objectives of the ECOSAI as:
"The organization of Supreme Audit Institutions of ECO countries, inspired by the principle of equality of all member institutions and by the respect for the legal frameworks governing each member institution and seeking the possibility of affiliating to International Organization of Supreme Audit Institutions (INTOSAI), shall aim at; 

a) exchanging knowledge and skills in government auditing among member institutions; 
b) sharing experience in the practice and development of auditing; 
c) promoting development of auditing standards;
d) fostering mutual collaboration and brotherhood among the staff of member institutions! 
e) developing information and database on government auditing practices of member SAIs;
f) encouraging joint research activities and transfer of knowledge in government auditing"

ECOSAI achieves its objectives through its Assembly, Governing Board and Secretariat. The Assembly, which is the supreme body of the Organisation, is composed of all members. Its first Assembly was held in Pakistan in 1994 and the last will be held at Tehran, Iran on June 9-10, 2003

The Governing Board is composed of five members (SAIs of Iran, Pakistan, Azerbaijan, Kyrgyzstan and Turkey). They meet at least once a year.

As for the Auditors of ECOSAI, currently the task is assumed by the heads of SAIs of Azerbaijan and Kyrgyzstan.