Two-time defending champion Martina Hingis defeated Amélie Mauresmo in the final, 6–2, 6–3 to win the women's singles tennis title at the 1999 Australian Open.

With the win, she joined Margaret Court, Evonne Goolagong, Steffi Graf, and Monica Seles as the only women to win three consecutive Australian Open titles.

Hingis also became the only woman to win three consecutive Australian Open titles in singles and doubles simultaneously.

Prior to her semifinal defeat to Hingis, Seles was undefeated in 33 matches at the Australian Open, dating back to her tournament debut in 1991, the longest undefeated winning streak at one tournament by a woman in the Open Era.

[1] This was the last Australian Open appearance for four-time champion Graf, who was defeated by Seles in the quarterfinals.