The 40-year-old will instead concentrate on his role assistant manager at the club after being confirmed as Louis Van Gaal's number two.
"Today is a fantastic day for Manchester United. Louis van Gaal is a great appointment and let me begin by telling you how delighted I am to be working with someone of his calibre. His credentials are second to none and I’m positive the club will thrive under his leadership over the coming years," he said.
"I would also like to take this opportunity to announce my retirement from professional football and embark upon a new and exciting chapter in my life, as assistant manager of Manchester United. I am immensely proud, honoured and fortunate to have represented the biggest club in the world 963 times and Wales 64 times.
"My dream was always to play for Manchester United, and although it saddens me to know I won’t be pulling on a United jersey again as a player, I have been lucky enough to have fulfilled that dream playing with some of the best players in the world, working under an incredible manager in Sir Alex Ferguson, and most of all, playing for the greatest fans in world football. I have always felt and appreciated your support."
Giggs scored 114 goals and won 13 titles, four FA Cups, four League Cups and two Champions Leagues with Manchester United.
- Sports & Recreation
- Manchester United
- Louis Van Gaal
- assistant manager