The university was established in 1917 with four original faculties: Medicine, Public Administration, Engineering, and Arts and Science.
Of the four, only the faculties of Engineering and of Arts and Science remain with the university, while many others have been created or added.
The Faculty of Arts and Science was newly established to cover non-specialized areas of knowledge.
The Faculty of Public Administration was merged with the Law School of the Ministry of Justice to become the Faculty of Law and Political Science in 1933, and was transferred to the newly established University of Political and Moral Sciences (now Thammasat University) in 1934.
The faculties are tasked with education, research, student development, and academic services in their respective fields, while the colleges hold similar roles but are limited to postgraduate studies.