The Coal Miner's Daughter singer will collect the Crystal Milestone Award - her 13th ACM trophy - at the ceremony, while Bryan has been named the winner of this year's Gene Weed Special Achievement Award, which acknowledges "unprecedented, unique and outstanding individual achievement in country music".
Other early winners include Eric Church, who has been named the 2015 ACM Award winner of the Jim Reeves International Award, and his songwriting partner Luke Laird, who is the 2015 ACM Songwriter of the Year.
Meanwhile, country supergroup Alabama have been named the 2015 ACM Career Achievement Award winners.
The special awards winners will be acknowledged at the ninth annual ACM Honors event in September (15).
Meanwhile, the ACM Awards, which will be co-hosted by Bryan, will take place in Texas on 19 April (15).
Miranda Lambert and Dierks Bentley lead the pack of nominees.