Feng produced a solid swinging exhibition incorporating a number of impressive somersaults, twists and handstands to earn 15.966 as all of his main rivals fluffed their routines.
So confident was Feng about his performance, he quipped: "I wanted the gold, I felt the judges were under more pressure than me."
Brothers Kazuhito and Yusuke Tanaka had raised the possibility of completing a Japanese one-two after earning the top two qualifying scores but both wobbled and wavered across the bars on Tuesday and left empty handed after finishing fourth and eighth respectively.
Feng, the 2010 world champion, surpassed Germany's Marcel Nguyen by 0.166 of a point while Frenchman Hamilton Sabot picked up a surprise bronze.
Feng's success gave the Chinese men's gymnastics team their third gold of the London Games.
After team mate Zhang Chenglong fell off the bars attempting a twist, Feng was determined to make sure China maintained their supremacy on the apparatus following Li Xiaopeng's success in 2008.
He packed his performance in with straight line handstands, soaring somersaults into upper arm catches and when he finished off with a doubled piked somersault dismount, he almost drowned out the cheers of 13,000 fans with an almighty roar.
Nguyen was also left smiling when he completed his error-free display with a rarely seen full-twisting double-back dismount and sent up a puff of chalk as he smacked his hands together in delight.
But his joy was nothing compared to the wide-eyed expression on Sabot face, who produced the performance of his life despite carrying a hand injury.
The Frenchman could not believe his luck as he stood on the podium, licking his lips and grinning from ear-to-ear with the bronze medal round his neck.
"I didn't feel anything (In my hand)... during the competition the adrenaline took over, I just knew what I had to do. It's been great."
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