Debbie Dunn (born 26 March 1978) is an American sprinter, who specializes in the 400 metres.

Originally from Jamaica, she attended Fairmont Heights High School in Maryland, then Norfolk State University,[1] and became an American citizen in 2004.

In the 4 x 400 m relay event she finally outpaced everybody, grabbing the gold medal together with teammates Allyson Felix, Lashinda Demus and Sanya Richards.

She earned a second gold medal for the 4 x 400 m relay, in which the U.S. team consisting of Dunn, DeeDee Trotter, Natasha Hastings and Allyson Felix finished in 3:27.34.

In July 2012, it was announced that she tested positive for a banned substance.