Six Apollo astronauts drove lunar rovers on the Moon.
The drivers were David Scott and James Irwin on Apollo 15, John Young and Charles Duke on Apollo 16, and Eugene Cernan and Harrison Schmitt on Apollo 17. Each mission carried one battery-powered Lunar Roving Vehicle, and both surface astronauts operated it during their excursions.
Apollo 15 was the first mission to deploy a rover, followed by Apollo 16 and Apollo 17. The vehicles allowed crews to travel much farther from their lunar modules than earlier astronauts could walk. They also carried scientific tools, cameras, communications equipment, and collected samples from multiple locations.
This total counts astronauts who actually drove a rover, not the number of rover vehicles or the number of missions. Three missions used rovers, with two drivers on each mission. Apollo 11, 12, and 14 relied on walking and hand-pulled equipment instead.