His medal is also Italy's 500th at the Paralympic games.
After winning silver in the 400m freestyle (S9), Morlacchi scooped gold in the 200m individual medley (SM9) on Sunday, his time of 2:16:72 allowing him to beat Hungarian Tamas Sors and Australian Timothy Disken.
“This is the top of the world,” Morlacchi said, according to Gazzetta dello Sport. “I had fun. I haven't really realized what I have done yet.”
He celebrated by punching the water and blowing a kiss to his supporters in the stands, but said that he never cries at a win. "My job is to make others emotional."
The president of Italy's Paralympics Committee, Luca Pancalli, said: "I'm indescribably happy. Federico deserves everything, he's a phenomenal guy. This medal was a masterpiece."
It was the fifth Paralympic medal of his career for 22-year-old Morlacchi, who is from the Varese region and went home from the 2012 games in London with three bronze medals.
The S9 category is for athletes with "severe weakness in one leg" and Morlacchi has hypoplasia (incomplete tissue development) in his left leg. He initially took up swimming for rehabilitation as a young child.