UPSU has about 30,000 members
The students' union bar at the University of Plymouth has been recognised for its efforts in promoting the responsible sale of alcohol.
The Best Bar None competition is run by the National Union of Students (NUS) to assess how bars handle student safety.
More than 70 UK students' unions were recognised, but the University of Plymouth Students' Union (UPSU) took top honours as the overall winner.
UPSU scored 97.9% of the measured criteria assessed over five months.
It is the sixth year the awards have been held.
The NUS said at a time when negative perceptions of the licensed trade were prevalent, particularly with regards to student drinking, the Best Bar None format was a positive way to improve standards and perceptions of alcohol retailing.
The NUS said for the past three years, the Best Bar None scheme had successfully encouraged unions to provide free drinking water to customers.
James Redfearn, UPSU's vice president, said being crowned national champions was a testament to the dedication of staff and "their constant efforts to make our venue a safe and responsible environment".
With about 30,000 student members, UPSU is one of the largest student unions in the UK and is an accredited member of Plymouth City Safe scheme - an equivalent scheme run locally by Devon and Cornwall Police.