The 33-year-old former Bradford and Wigan prop, who joined Huddersfield at the start of the season, will remain at the John Smith's Stadium as part of head coach Paul Anderson's backroom team.
Fielden, who is still the game's most expensive player following his move to Wigan from Bradford for a transfer fee of around £440,000 in 2006, appeared in nine of the Giants' opening 11 matches of Super League XVIII before picking up a knee injury at Castleford in April.
The knee then became infected and Fielden has decided to hang up his boots.
"I am making this announcement now to put all speculation to bed and want us all to concentrate on the next few games for the club which are simply massive," Fielden said.
"I said I came here to win things and that remains my aim. The club have been superb with me and this freak infection is just typical of the luck of I have had for a while now.
"We have explored every avenue possible and I have trained constantly to get back on the field but it's not going to be so I have to move on and work off the field to help us achieve.
"I am grateful of the opportunity Paul has given me and, having got over the shock of the knee ruling me out, I'm now excited about the next chapter in my career.
"I really have enjoyed being here - more so than I expected if truth be told - and it really is a club that has great potential so I guess I am lucky really that I can stay on and start learning and working under Paul and his team."
Fielden won 25 caps for Great Britain and played seven times for England, most recently in the 2010 Four Nations Series in Australia and New Zealand, and was widely regarded as the best forward in the game at the time of his move to Wigan.
Anderson, who was a team-mate of Fielden at Bradford, said: "I have had the pleasure of playing with, against and coaching Stuart and throughout his career he has been the ultimate professional.
"The news is disappointing for all concerned but it's a credit to Stuart's professionalism the way he has accepted the decision and he's now fully focused on his new coaching role.
"He is a great addition to the Giants coaching team as he is a Super League legend with such a decorated medal cabinet and his experience will be invaluable going forward."
- Sports & Recreation