Evans, who leaves with immediate effect, is being replaced by Stuart MacFarlane, InBev's global director of customer standards.
The circumstances of Evans' departure are not yet clear, but in a statement he said he was "seeking new challenges", having been made president of InBev UK and Ireland in 2006.
Before this, he was vice-president of commercial strategy at InBev, and was promoted to vice-president of brands in 2003.
His replacement, MacFarlane, joined InBev in 1992 and has held various sales and marketing roles in that time.
MacFarlane said: "I would like to pay tribute to the significant contribution that Richard has made to the business during his 14 years of service and recognise his achievements and the work that he has put into InBev."
Last week, InBev said it was going to axe its Bock brand from the Artois range and replace it with Eiken Artois, its new premium lager.
The company said it hoped that the launch of Eiken Artois will boost its flagship Stella Artois brand, which has had its premium positioning called into question recently following the news that Young's was delisting it from its pubs for not been premium enough.