1990 Canadian Open – Women's singles

Steffi Graf defeated Katerina Maleeva in the final, 6–1, 6–7, 6–3 to win the women's singles tennis title at the 1990 Canadian Open.

Martina Navratilova was the reigning champion, but chose not to participate.

Seeds
The top eight seeds received a bye to the second round. • # Steffi Graf (champion)

• # 🇦🇷 Gabriela Sabatini (semifinal)

• # 🇧🇬 Katerina Maleeva (final)

• # Manuela Maleeva-Fragniere (quarterfinal)

• # Natalia Zvereva (quarterfinal)

• # 🇺🇸 Jennifer Capriati (quarterfinal)

• # 🇫🇷 Nathalie Tauziat (semifinal)

• # 🇦🇹 Barbara Paulus (third round)

• # 🇨🇦 Helen Kelesi (third round)

• # 🇮🇹 Raffaella Reggi (third round)

• # Claudia Porwik (second round)

• # Manon Bollegraf (second round)

• # Larisa Savchenko (second round)

• # 🇫🇷 Julie Halard (first round)

• # 🇺🇸 Lori McNeil (third round)

• # Regina Rajchrtová (first round)