The women's 400 metres event at the 2015 Summer Universiade was held on 8, 9 and 10 July at the Gwangju Universiade Main Stadium.
Qualification: First 4 in each heat (Q) and next 4 fastest (q) qualified for the semifinals.
Qualification: First 2 in each heat (Q) and the next 2 fastest (q) qualified for the final.