After revealing a new rainbow-dyed hairstyle, she clocked 10.71 in front of a sparse crowd in the Qatari capital.
Jamaica's Fraser-Pryce, 32, powered to 10.71 seconds in Doha for her eighth world title while Asher-Smith's 10.83 is a new British record.
Two years after having her first child, Fraser-Pryce became the oldest woman to win an Olympic or world 100m title at 32 years old.
Dina Asher-Smith of Britain took silver at 10.83 ahead of Marie-Josee Ta Lou of the Ivory Coast at 10.90.
Defending champion Tori Bowie of the United States withdrew before the semifinals. No reason was given, but injuries have hampered her form over the last year.
Christian Coleman of the United States won the world championship gold medal in the men’s 100 meters Saturday, three weeks after avoiding a ban for missed drug tests.
Ivory Coast's Marie-Josee Ta Lou took bronze in 10.90.