Known as Beacon House, the Grade II listed building will be a flagship facility for the University after a £12 million investment.
The well-known building, on the corner of Queen’s Avenue and the Triangle, has been empty since Habitat closed in 2011.
After eight months of building work led by Midas Construction, the 2,643 square metre facility now boasts a study centre, complete with 388 study seats, 66 computers, social study spaces, a quiet study area and flexible group learning rooms.
The café will be open to the public seven days a week, as will the large reception area which provides a focal point for all visitors to the University.
The University says Beacon House will become a key part of the University's campus thanks to its location between the Students' Union and the central campus.
Professor Judith Squires, Pro Vice-Chancellor at the University of Bristol, said: "Beacon House is a really exciting addition to the University as the building is in such a prime position.
"It will accommodate, energise and inspire students in a welcoming and flexible environment, and showcase the best of the University to our visitors. As a site that promotes and celebrates learning we hope that it will become central to the University's engagement with its students and the wider city."
The building has been carefully designed to meet the needs of students who increasingly need flexible study spaces in addition to traditional libraries.
Beacon House features easily moveable furniture so that the purpose of different spaces can be changed, sound-insulated booths to ensure quiet study, and even wireless mobile phone charging points.
The project is the latest in a series of investments by the University in teaching and research facilities as part of its £525 million capital investment programme over 10 years.
Dr Jessica Gardner, Director of Library Services at the University of Bristol, said: "A great deal of work has gone into this project, and we've created a space which we hope students will really love.
"Although a traditional library will always be a core part of any university, the way young people choose to study is definitely changing and Beacon House has been designed with that in mind, offering both quiet and sociable learning spaces in a central location."
Beacon House, next to the Royal West of England Academy, was constructed in the 1850s and was formerly the Queen's Hotel before being used for retail purposes – Gardiners in the 1930s, Debenhams after the war and more recently Habitat, which closed in 2011.