0853 GMT November 21, 2019
The American, 22, claimed her 18th gold to surpass the overall medal record held by Vitaly Scherbo, BBC Sport reported.
She put in another sublime display to win her fourth gold of these championships with a score of 15.066 in Stuttgart, Germany.
China's Liu Tingting and Li Shijia took silver and bronze respectively.
Having won four gold medals and one bronze at Rio 2016, Biles now has 29 combined world championship and Olympic medals, four short of the record held by Scherbo who represented the Soviet Union, the Commonwealth of Independent States and Belarus in the 1990s.
Nikita Nagornyy completed a hat-trick of gold medals at the World Gymnastics Championships on Sunday by adding the men's vault title to his all-round and team success with Russia.
The 22-year-old snatched gold from defending champion and Russian teammate Artur Dalaloyan with a tiny winning margin of only 0.033 points while Ukraine's Igor Radivilov earned bronze in Stuttgart.
It was a repeat of Friday's all-round final where Nagornyy took gold and Dalaloyan, the men's 2018 world champion, finished with silver.
This was Nagornyy's third world title this week after also helping Russia win the men's team title alongside Dalaloyan.