Ismat Jahan (born 3 June 1960) is a Bangladeshi diplomat who is currently serving as the permanent observer of the Organisation of Islamic Cooperation to the European Union.

[1][2] A career diplomat of the 1982 batch of Bangladesh Civil Service (foreign affairs) cadre, Jahan had her education in the University of Dhaka with an honours and a master's in economics.

Following her appointment as ambassador to the Netherlands,[4] Jahan served as permanent representative of Bangladesh to the United Nations.

[6] In July 2016, she was appointed as the head the Organisation of Islamic Cooperation (OIC)'s Permanent Observer Mission to the European Union.

[8] Jahan is married to Johannes den Heijer, a Dutch professor of Arabic language and literature at the Université Catholique de Louvain in Belgium.