This paper explains how the Persian Muslim scholar Abu al-Raihan Muhammad Bin Ahmad al- Biruni, who lived during the mediaeval Islamic era, played as a role model in the social sciences and humanities, particularly in the study of Indology and religions. It begins with the biography of Al- Biruni, and his thoughts as well as his methods in the study of Indology and religions. Then, it examines his encyclopaedic account of Indology in Arabic which is translated by Edward C. Sachau in two volumes as Al-Biruni’s India. Descriptive method and textual approach are used to carry out the investigation of Al-Biruni’s teachings and works. It concludes with reflection on his significant pioneering work in the disciplines of comparative religion and Indology.