Independent publisher Clive Richardson launched The Audi Magazine in 1986 and has published it continuously since.
The car manufacturer reviewed the arrangement as it wanted to ramp up its print marketing efforts in line with its broader strategy, which includes a TV channel, and make the magazine more contemporary.
Northstar will publish the magazine in June, following a seven-way pitch with publishers chosen for their proven track record in automotive customer magazines, including Cedar Communications, John Brown and the incumbent.
Northstar also produces magazines for Honda F1, Mazda and Goodwood.