A match featuring the two best club sides in Asia was always going to be close and so it proved with the scores locked at 2-2 with three minutes of normal time remaining.
However, a quick-fire double from Javad Asghari and a strike from futsal legend Vahid Shamsaee secured the trophy for the tournament hosts.
Shamsaee had given Foolad the perfect start when he struck after two minutes before Mohammad Taheri side-footed into the roof of the net to put Hossein Afzali's side into a commanding position.
The 36-year-old Shamsaee then flicked a header just wide for Foolad but Al Sadd reduced the deficit with seven minutes of the half remaining when Errahmouni Bilal struck, much to the consternation of the vociferous home crowd.
The local fans were silenced again two minutes into the second half when Al Sadd equalised as Bilal clipped the ball over the onrushing Mostafa Nazari.
Foolad dug deep, though, as Taheri's shot from just outside the area was denied by Al Sadd keeper Faraj Rashid while Mohammad Keshavarz's long-range drive flew just wide before Shamsaee failed to score when one-on-one with Rashid in the 32nd minute.
The game looked destined to go to extra time but with three minutes left on the clock the stadium erupted as Shamsaee fed a pass to Asghari on the right and the forward hit a low effort beyond Rashid.
Victory was in sight when Asghari added another seconds later as he flicked a shot into the net following a quick counter before the game was put beyond Al Sadd in the 38th minute when Shamsaee broke quickly before slotting beyond Rashid's right.
Foolad then held onto possession to run down on the clock before the final whistle sparked scenes of jubilation amongst the home fans and the Foolad players.