See main article: 1990 Australian Open.
Two-time defending champion Steffi Graf defeated Mary Joe Fernández in the final, 6–3, 6–4 to win the women's singles tennis title at the 1990 Australian Open. It was her third Australian Open title and ninth major title overall.
The seeded players are listed below. Steffi Graf is the champion; others show the round in which they were eliminated.
See main article: 1990 Australian Open – Women's singles qualifying.