Driving a Ford Taurus, Burton covered the 1 1/2-mile speedway in 31.921 seconds, averaging 169.138 miles per hour, a bit shy of Matt Kenseth's qualifying mark set last year.
Burton set the race record of 135.118 mph when he won this event in 2000. He was sixth here last year and also has won a pair of Winston Cup events at this track.
"We revamped our Busch team in the offseason and brought in all new people," Burton said. "We just put in a huge effort and the team does a good job getting this car ready. Every lap we've made here at Las Vegas has been fast and competitive."
Trying to keep up with Burton will be Jimmy Spencer, who will start on the outside of the front row after clocking 169.051 mph in a Chevrolet Monte Carlo. Spencer won this race in 1998.
"I'm having a good time in NASCAR, I really am," Mears said. "These cars are much different than the Champ and Indy cars I was driving. I'm still in a big learning curve with this deal."
Green, the pole winner last week, won this race from the pole in 1997.