The women's singles tournament of the 2021 BWF World Championships took place from 12 to 19 December 2021 at the Palacio de los Deportes Carolina Marín at Huelva.

[1] P. V. Sindhu was the defending champion, but she lost to Tai Tzu-Ying in the quarterfinals.

This also guaranteed Tai Tzu-Ying's first medal of world championships.

The seeding list is based on the World Rankings of 23 November 2021.

[2]