The single deck bus will primarily run along the lime 2 route, which serves Mears's village Burghfield Common, near Reading, but will also be available for use on other routes in the town.
It comes after a fake golden postbox was installed in his village in August.
Mears and his diving partner Jack Laugher won the men's synchronised 3m springboard event.
He described seeing himself pictured on a bus as a "surreal experience".
"My old friendship group use this service, so it's going to be weird for them getting on the bus and seeing me on the side of it," he said.
He added that he hopes the younger generation in the town will be inspired by his achievements in Rio and for the sport of diving.
Jake Osman, of Reading Buses, said: "After the great exploits of London 2012, the gold medal winning athletes were celebrated with gold post boxes in their home towns. However, this was only for those Olympics.
"As Chris will not get a golden post box in Burghfield Common we thought we could step up and give Chris something to demonstrate that the people of Burghfield, and Reading are proud of his achievements."
The bus was unveiled at the Pride of Reading Awards on Friday.
A gold bus has been created for Olympic gold medallist Chris Mears in tribute to his Rio 2016 success.