Bryan immediately overshadowed top winner Miranda Lambert's big night by beating out some of country music's top performers, including Lambert and her husband Blake Shelton, Jason Aldean and two-time entertainer of the year Taylor Swift in an upset that few would have predicted because of his relatively recent move into the spotlight.
The 36-year-old Georgia native recently began headlining his first arena tour and was the co-host of this year's show.
"I don't know what to say guys," Bryan said as members the audience shouted "Luke.
After an emotional speech, Bryan's co-host Blake Shelton held his partner up and joked that he won in his "first and last year as co-host" of the awards.
Bryan is the first male winner of the award since 2007 when Kenny Chesney won the first fan-voted award. Swift and Carrie Underwood have won two apiece since then.
Bryan's win will be the talk of Las Vegas Sunday night but Lambert again walks away as the academy's trophy magnet.
She won her fourth straight female vocalist award and picked up three trophies for her hit song "Over You"—one for single record of the year and two for song of the year. She was performer of the song and co-wrote the song with Shelton.
"Over You," written about Shelton's late brother, won song of the year at the Country Music Association Awards last November as well.
"As a songwriter, having your song and your lyrics recognized by your peers is pretty much as good as it gets," Lambert said. "And I'm so thankful for being in this genre of country music, every single time someone's nominated, I just cheer, because I love everybody to death. So thank you for accepting me as a song writer, not just as a singer, because that means the world to me."
Eric Church won two awards, including album of the year, and was tied with Jason Aldean, Little Big Town and Florida Georgia Line in overall win total.
Church, this year's top nominee, also won vocal event of the year for his collaboration with Aldean and Luke Bryan for their collaboration on "The Only Way I Know" and performed his somber but powerful song "Like Jesus Does" with only an acoustic guitar and a backup singer.
"I think my career is going to be pre-'Chief' and post-'Chief,'" Church said.
Aldean, country's top-selling male act, won male vocalist of the year. Little Big Town had wins for vocal group and video of the year. Florida Georgia Line won for new artist and were previous winners in the new vocal duo/group category. And husband and wife Shawna and Keifer Thompson continued their feel-good story as Thompson Square won its second straight vocal duo of the year award.
Shawna Thompson gave a shoutout to her mother from stage.
Tears came to her eyes backstage as she explained that her father had recently passed away and she wanted to acknowledge her mother during her acceptance speech to support her.
"She's just having a really hard time," she said.
The night was full of colorful performances, but the anticipation of Garth Brooks and George Strait performing together overshadowed almost everything else. The two paid tribute to the late Dick Clark, the executive producer of the show since 1979 who passed away a year ago.
Brooks appeared on stage in flannel shirt and black cowboy hat with a Fu Manchu to perform his hit "The Dance" before Strait joined him for "The Cowboy Rides Away."
Reba McEntire introduced the two and paid tribute to Clark, momentarily breaking down as tears appeared in her eyes.
"He would slap me if he saw me crying up here," she said.
Shelton kicked the show off with his new single "Boys 'Round Here," a hip-hop-flavored ode to redneck swag.
Strait made his first appearance of the night earlier, singing "Give It All We Got Tonight." Lady Antebellum debuted new song "Downtown" and Charles Kelley finished off the song by rubbing pregnant trio-mate Hillary Scott's belly. Carrie Underwood stepped out of a black Cadillac parked on stage as she started her song, "Two Black Cadillacs."
Lambert appeared later with a fiery, diamond-studded rendition of her recent hit "Mama's Broken Heart."
John Mayer joined Paisley for a guitar summit on "Beat This Summer" and Taylor Swift and Keith Urban joined Tim McGraw on stage for "Highway Don't Care," which Urban finished off with a scorching guitar solo.
AP Writer Hannah Dreier contributed to this report.
Follow AP Music Writer Chris Talbott: http://twitter.com/Chris—Talbott.