The women's 100 metres T12 event at the 2020 Summer Paralympics in Tokyo, took place between 1 and 2 September 2021.

The T12 category is for athletes with visual impairment.

Athletes in this category will generally have some residual sight, the ability to recognise the shape of a hand at a distance of 2 metres and the ability to perceive clearly will be no more than 2/60.

T12 athletes commonly run with guides.

Prior to the competition, the existing records were as follows:[1] Heat 1 took place on 1 September 2021, at 19:37:[2] Heat 2 took place on 1 September 2021, at 19:45:[3] Heat 3 took place on 1 September 2021, at 19:53:[4] Heat 4 took place on 1 September 2021, at 20:01:[5] Semi-final 1 took place on 2 September 2021, at 11:06:[6] Semi-final 2 took place on 2 September 2021, at 11:14:[7] The final took place on 2 September 2021, at 19:20:[8]