Formerly known as St. Mary's University College, St. Mary's University is a public institution of higher education in South West London's suburban town of Twickenham. Established as a university college in the year 1850, it is acknowledged as the oldest university in the UK with an affiliation to the Roman Catholic Church. In 2014, the Privy Council awarded it the university status under its current name.

It has affiliations from the International Federation of Catholic Universities and the Association of Catholic Colleges and Universities. The university is also associated with GuildHE and the Cathedrals Group.

St. Mary's University has a beautiful campus that features a wide range of facilities to support excellent learning and stay experience for the students. The SU Hub on the first floor of the Students' Union (SU) building has a shop and a small common room with sofas and laptops. SU building also has the SMUC Radio studio and a post room for resident students.

Opened in 2008, the Refectory and Shannon Suite house a large seating area with kitchen facilities, a conference centre and three meeting rooms with AV provision.

 The site also features a wellness centre, library, printing facilities and several dining points. The Sports Centre is home to a state-of-the-art fitness suite that has 35 equipment stations and ten bespoke lifting platforms. The centre also has a high-performance sports hall consisting of a range of training and athletic facilities including four cricket lanes, six badminton courts and three courts for basketball, netball and handball. Other recreational facilities on the campus include a dance studio, tennis hall, grass pitches and athletic tracks.

The university provides accommodation to the students in its on-site housing facility with catered or self-catered, single rooms or shared rooms. It also runs several private residence halls located very close to the university and major amenities like shopping complexes, entertainment hubs, restaurants and nightlife spots.

St. Mary's University comprises two faculties that offer undergraduate, postgraduate and doctorate programmes in different disciplines of humanities, social sciences, education, sports, health and applied sciences. It also has an institute that extends education in theology. Apart from this, the institution gives a range of short courses on weekends and during the evenings.

At present, over 5,535 students are pursuing their degrees from the university. It has more than 200 academics, administrative affiliates and helping staff members on the roll.

The university has a comprehensive list of alumni living across the globe. Some notable names in the list are Clara Amfo (Radio Presenter), Robert Thomas Beck (Actor), David Bedford (Athlete), Stephen Henry (Educator, Theatre Producer and Director), Peter William Postlethwaite (Actor), Jonathan Holloway (Theatre Director and Playwright), James McEvoy (Educationist), Aled Euros Miles (Businessman), Leslie Arnold Reed (Football Coach), Toby Gold (Paralympic Silver Medallist), Thomas Patrick O'Connor (TV Presenter, Actor and Comedian), Gordon Pirie (Athlete), Moe Sbihi (Olympic Bronze Medallist Rower) and Georgia Steel (TV Personality and Actress.