Moojan Momen was born in Iran but was raised and educated in England, attending the University of Cambridge. He has a special interest in the study of Shi'i Islam and the Bahá'í Faith, both from the viewpoint of their history and their doctrines. In recent years, his interests have extended to the study of the phenomenon of religion.

He has contributed articles to encyclopaedias such as Encyclopaedia Iranica and The Oxford Encyclopedia of the Modern Islamic World as well as papers to academic journals such as International Journal of Middle East Studies, Past and Present, Religion, Baha'i Studies Review, and Iranian Studies. He is a Fellow of the Royal Asiatic Society.