Forty-one athletes of thirty nations participated in the five heats of the first round on 21 August.
Kemi Adekoya of Bahrain set an Asian record of 53.56 seconds.
Twenty-four athletes competed in the three heats of the semifinals on 22 August.
Bol remained unbeaten in all her hurdles races since the 2022 final and her world-leading time of 51.45 s was almost 2 seconds faster than anyone else had run this year.
Other medal hopefuls were Bahraini Kemi Adekoya, who set Asian records in both the preliminary heats and semi-finals, and 2019 bronze medalist Rushell Clayton from Jamaica, who set a personal best in the semi-finals.