"After a long thought-out process and speaking with my family I've decided to announce my retirement from boxing.
"I've achieved all my life dreams and ambitions in the sport and it is the right moment for me.
"I'm 30 years of age and it is time to step on and face new challenges," he told RTE.
Dunne defeated Ricardo Cordoba in Dublin last March to win the WBA World Super-Bantamweight title as the highlight of his career. He subsequently lost the title.
"There have been so many highs in my career but to pick one out you'd have to pick the night against Cordoba.
"It is the stuff dreams are really made of. That night was, I suppose you could say, like a movie script.'
He added: "The easiest thing in the world would have been to climb through the ropes and fight again but honesty has always been very important to me and I am being honest to myself, to my family and to my supporters with this decision.
"The great Irish fans that traveled on the journey to a world title belt with me deserved better than to pay their hard earned cash just to see me go through the motions. I could never do that to them.
"Thankfully I have realized all my dreams and achieved all my goals since I followed my dad into boxing.
"To win a world title is something I will never forget and something I am so proud of and I would like to thank everyone who helped make that possible.
"This is a sad day for me and for my family but it is also an exciting day and a new start in my life, one I am really looking forward to."
Dunne's manager and promoter Brian Peters paid tribute to the boxer and offered full support of the move:
"Bernard's decision to hang up his gloves has my full backing and support.
"We've had a number of discussions since Bernard lost his World title last September and having scaled the heights he has as a World and European Champion he believes that now is the right time to walk away and I am 100% behind that decision.
"I think it would only be fair to thank his professional trainers, Harry Hawkins and Freddie Roach, his sponsors Martin Donnelly and Hunky Dorys and of course Glen Killane and RTÉ who helped to turn Bernard into a household name across the country.
"I know that Bernard's achievements will ensure he forever holds a place in the hearts of the Irish sporting public and I know that with his engaging personality he will prove just as popular in retirement as he did during his boxing career."