Pete Sampras defeated the defending champion Patrick Rafter in a rematch of the previous year's final, 7–6(9–7), 6–3 to win the singles tennis title at the 1999 Cincinnati Masters. With the win, Sampras reached his fourth title in this season, after previously winning at London (Queen's), Wimbledon and Los Angeles.

Seeds

The top eight seeds received a bye to the second round.

Draw

Finals

Top half

Section 1

Section 2

Bottom half

Section 3

Section 4

Qualifying

Qualifying seeds

• # 🇫🇷 Arnaud Clément (qualified) • # 🇦🇺 Mark Woodforde (qualified) • # Ramón Delgado (qualified) • # 🇩🇪 Bernd Karbacher (qualifying competition) • # 🇦🇺 Wayne Arthurs (qualified) • # 🇨🇿 Martin Damm (qualifying competition) • # Ivan Ljubičić (qualified) • # Wayne Black (qualified) • # 🇨🇦 Sébastien Lareau (qualifying competition) • # 🇧🇾 Max Mirnyi (qualifying competition) • # 🇩🇪 Axel Pretzsch (qualified) • # 🇮🇹 Mosé Navarra (qualifying competition) • # 🇦🇺 Todd Woodbridge (first round) • # 🇺🇸 Alex O'Brien (qualifying competition)

Qualifiers

• # 🇫🇷 Arnaud Clément • # 🇦🇺 Mark Woodforde • # Ramón Delgado • # 🇩🇪 Axel Pretzsch • # 🇦🇺 Wayne Arthurs • # Wayne Black • # Ivan Ljubičić

Qualifying draw

First qualifier

Second qualifier

Third qualifier

Fourth qualifier

Fifth qualifier

Sixth qualifier

Seventh qualifier