Second place went to Emma Wareus of Botswana, and Adriana Vasini of Venezuela came third.
The host country’s own contestant, Tang Xiao, also was among the final five.
According to a brief biography on the Miss World website, Mills calls Louisville, Kentucky, her hometown, and she recently graduated from high school. She would like to become a teacher.
“I’ve never met a stranger and enjoy meeting new people,” she says in the bio.
For the final, she was wearing a shimmering ivory-colored dress slit up the leg.
Mills takes over the title from Kaiane Aldorino of Gibraltar, who was named Miss World 2009 at a ceremony in South Africa last December.
Women from more than 100 countries participated in the contest, organizers said.
This is the 60th year of the Miss World Competition, and organizers brought back contestants from past decades to give the night a retrospective theme.
