The 26-year-old, who had claimed virtually every other title in an utterly dominant half decade including three world championship gold medals, clocked 12.99 seconds.
"It means the world to officially have it complete," Holloway told reporters. "To complete the career Grand Slam is what I've been wanting. I'm beside myself right now. So happy about everything going on."
U.S. teammate Daniel Roberts lunged at the finish line before tumbling to the track to claim silver in 13.09 seconds, beating Jamaica's bronze medallist Rasheed Broadbell by three-thousandths of a second in a photo finish.
Holloway, surprisingly beaten by Jamaica's Hansle Parchment at the Tokyo Olympics, had downplayed talk that he desperately needed a victory in Paris.
"I knew I was in shape, I knew I was capable of completing this feat. I officially did it," said Holloway, who jokingly wiped away fake tears after ringing the stadium's victory bell.
"I'm looking forward to what's to come. The future is so bright. Everything else that I can do, I know it's going to be great."
What is to come could well be a world record. His career best time of 12.81 is just a hundredth off the record set by American Aries Merritt in 2012.
"I've been hurdling so well this year, I'm in great shape, I just want to keep this going," he said.
As often happens in Holloway's races, the mystery was who would come second, and there were tense moments before the silver and bronze medallists' names flashed up on the screen.
"I've got battle scars from that race," Roberts said. "It was very intense, I was hitting hurdles. But I made up my mind that I wasn't going to let that stop me, I was going to keep going, keep fighting, run through that line.
Broadbell was thrilled with the bronze.
"I saw my dad crying," he said. "I know he feels good that all the dedication has finally paid off. I know he's not going to sleep for probably a week."
Tokyo champion Parchment finished eighth.
