The 32-year-old blonde beauty, who stunned in a plunging yellow gown, also picked up two awards at the ceremony at the MGM Grand in Las Vegas, reported Female First.
Lambert won the award for female vocalist for the seventh consecutive year and was also victorious in the vocal event of the year category for her "Smokin and Drinkin" collaboration with Little Big Town.
At the ceremony, hosted by Dierks Bentley and Luke Bryan, Lambert also performed "Tush" while her former husband Blake Shelton opened the show with his song "Came Here To Forget", which is reportedly inspired by his new girlfriend Gwen Stefani.
Meanwhile, Chris Stapleton was the big winner on the night, taking home a total of four awards, including male vocalist of the year, new male vocalist of the year, album of the year for "Traveller" and song of the year for "Nobody to Blame".