The 2017 NASCAR Xfinity Series was the 36th season of the NASCAR Xfinity Series, the second-tier professional stock car racing series sanctioned by NASCAR in the United States. The season began with the PowerShares QQQ 300 at Daytona International Speedway and ended with the Ford EcoBoost 300 at Homestead-Miami Speedway. Daniel Suárez was the defending drivers' champion while Toyota was the defending manufacturer's champion, although Suárez couldn't defend his title due to him racing in the Monster Energy NASCAR Cup Series.
During the season, races were broadcast by Fox Sports and NBC Sports for the third consecutive year.
William Byron of JR Motorsports won the driver's championship with a third-place finish in the season finale. Team Penske won the owner's championship while Chevrolet won the manufacturer's championship.
This was the second year that the Xfinity Series (and the Truck Series) had a playoff system. Two of the four "championship 4" drivers (who are shown below), were the same as last year's, the only differences being William Byron and Daniel Hemric were in it instead of Daniel Suárez and Erik Jones, who both moved up to the Cup Series full-time in 2017. Also, three of the four of them (Byron, Sadler, and Allgaier) all drove for JR Motorsports. As Hemric, the other driver in the "championship 4", drove for Richard Childress Racing, that meant that the "championship 4" was composed entirely of Chevrolet drivers. Also ironically, Sadler and Allgaier both ended up finishing in the same positions in the standings as they did in 2016, second and third, respectfully.