The Irish musician, who won the last series with his act Andrea Begley, announced today (July 16) that he will not be returning for a third year due to recording commitments with The Script.
"I had two wonderful seasons on The Voice and as everybody knows I gave it my heart and soul and couldn't be more proud of the show and what we have achieved," he wrote on Twitter.
"My focus will be on The Script moving forward as we are about to embark on the most important part of our career as a band."
The BBC confirmed the news on its official Twitter, writing: "Danny O'Donoghue, will not be returning to @BBCTheVoiceUK for next year's series due to recording commitments with The Script.
"Danny has been a star on #TheVoiceUK but we understand that he has to focus on his music career - The Script have a busy year ahead.
"We are very sorry to see Danny go but wish him and the band the very best and hope they will come back and perform for us next series."
The corporation added: "The full coaches' line-up for the third series of #TheVoiceUK will be announced in due course."
Jessie J revealed that she would also be leaving The Voice UK less than two weeks ago.
It is not yet known if will.i.am and Sir Tom Jones will remain on the panel for series three.
Watch Danny O'Donoghue talk to Digital Spy about The Voice UK, X Factor and more last year below: