The gymnast, nicknamed 'king of parallel bars' for his dominance on the apparatus, earned a staggering 16.200 points, head and shoulders above the rest.
Illia Kovtun took silver with 15.500, earning Ukraine theirfirst podium finish in the sport in Paris. Japan's Shinnosuke Oka, who won gold in the team and all-around events, took the bronze with 15.300.
During a masterful routine, Zou kept his arms and legs fully extended and steady as a rock and he drew applause from Kovtun every time he nailed a difficult move.
After sticking his dismount, the three-times parallel bars world champion pumped his arms in the air, smiling broadly and embracing his teammate Zhang Boheng, who came in fourth.
Kovtun, who will walk away from Paris with Ukraine's only medal in the sport, expressed disbelief and joy at his second-place finish.
"I am very, very happy," the 20-year-old said. "It was my last chance to win a medal and I got it.
"I didn't expect this to happen. I still haven't realised what I have achieved. I'm very proud of myself and being able to win this medal for my country, Ukraine."
Former Ukrainian President Petro Poroshenko congratulated the gymnast on X, writing: "Another addition to the Ukrainian Olympic treasury!... Thank you for your skill and craft! We wish you new victories."
