1998 du Maurier Open
Date	August 3–9 (men) August 17–23 (women)
Edition	109th
Surface	Hard / outdoor
Champions
Men's singles
Patrick Rafter[1]
Women's singles
Monica Seles
Men's doubles
Martin Damm / Jim Grabb[2]
Women's doubles
Martina Hingis / Jana Novotná
← 1997 · Canadian Open · 1999 →

The 1998 du Maurier Open was a tennis tournament played on outdoor hard courts. It was the 109th edition of the Canada Masters and was part of the Super 9 of the 1998 ATP Tour and of Tier I of the 1998 WTA Tour. The men's event took place at the National Tennis Centre in Toronto in Canada from August 3 through August 10, 1998, while the women's event took place at the du Maurier Stadium in Montreal in Canada from August 17 through August 23, 1998.

Finals

Men's singles

Patrick Rafter defeated Richard Krajicek 7–6^(7–3), 6–4

• It was Rafter's 4th title of the year and the 11th of his career. It was his 1st career Masters title.

Women's singles

Monica Seles defeated Arantxa Sánchez-Vicario 6–3, 6–2

• It was Seles' 1st title of the year and the 47th of her career. It was her 1st Tier I title of the year and her 8th overall.

Men's doubles

Martin Damm / Jim Grabb defeated Ellis Ferreira / Rick Leach 6–7, 6–2, 7–6

• It was Damm's 3rd title of the year and the 14th of his career. It was Grabb's 3rd title of the year and the 25th of his career.

Women's doubles

Martina Hingis / Jana Novotná defeated Yayuk Basuki / Caroline Vis 6–3, 6–4

• It was Hingis' 12th title of the year and the 37th of her career. It was Novotná's 9th title of the year and the 102nd of her career.