Button will join seven-time NASCAR Cup champion Jimmie Johnson and 2010 Le Mans winner Mike Rockenfeller in the Garage 56 line-up.
Garage 56 is the entry that the Automobile Club de l'Ouest sets aside for the “technology of tomorrow and beyond” of innovative machinery.
The entry – a modified version of the Next Gen Chevrolet Camaro ZL1 race car – is a collaboration of NASCAR, HMS, Chevrolet, IMSA, and Goodyear.
The project was first announced in March with the debut at the 2023 Le Mans 24 Hours an homage to NASCAR founder Bill France Sr, who first took stock cars to the French endurance classic almost half a century ago.
“As a lifelong racing fan, I have always dreamed of racing certain cars, with and against certain drivers and competing in certain events,” Button, who retired from F1 at the end of 2016, said.
“In June, a number of those dreams will come true in one event when I get to bring NASCAR to the world stage alongside my pals Jimmie and ‘Rocky’ for the 100th anniversary of the most prestigious race in the world.
"I’m really looking forward to sharing this journey with NASCAR, Hendrick Motorsports, Chevrolet and Goodyear, and current and future NASCAR fans from around the world.”
According to NASCAR, all three drivers of the Garage 56 line-up will take part in a two-day test next week at Daytona International Speedway.
The initial test car used in August at Road Atlanta, which was built by IMSA team Action Express Racing, has been replaced by the Hendrick car has been running since November, featuring revised chassis, engine, suspension and bodywork.
Jeff Gordon, who was expected to be part of the program, is said to have been "good" with the decision for him not to be involved.