The 24-year-old broke down in tears after matching the achievement of weightlifter Hidilyn Diaz, who won gold at the Covid-delayed 2020 Tokyo Games.
"I just went for it, I didn't hesitate," said Yulo.
The former world champion perfectly executed his routine, ending with a sure-footed landing to score 15.000 points. It sealed the first gymnastics Olympic medal ever for the Philippines.
Defending champion and world titleholder Artem Dolgopyat of Israel was pushed into silver with 14.966.
"The past months (in general) were hard. I had some problems with my leg and also the training was difficult," said the 27-year-old Dolgopyat.
"It's a hard time in Israel. I tried to do my best in the competition, to show everyone that Israel is very strong and that we can win medals."
Britain's Jake Jarman, who had scored highest in qualifying a week ago, achieved 14.933 to take bronze at Bercy Arena.
Yulo had warned he was "shooting for the stars" in Paris after missing out on the podium in Tokyo.
And his acrobatic and technically difficult routine proved a hit, scoring higher than the 14.766 he had garnered in qualifying.
"I'm so overwhelmed. I'm feeling grateful for having this medal and for God. He protected me, as always," said Yulo, who has a chance of another medal in the vault final on Sunday.
"He gave me the strength to get through this kind of performance and perform this well."
China's Xiao Ruoteng, the Tokyo floor bronze medallist, slumped to last in the eight-man final after hopping out of bounds after his opening jump to finish with 13.933.
Xiao had been bidding for gold to add to his silver in the men's team event and bronze in the all-around competition at the Paris Games.
