Venus Williams defeated Conchita Martínez in the final, 2–6, 6–2, 6–1 to win the singles tennis title at the 2004 Family Circle Cup.

It was Williams' 30th career title.

Justine Henin-Hardenne was the reigning champion, but did not compete this year due to hypoglycemia.

The first nine seeds received a bye into the second round.