1989 Suntory Japan Open Tennis Championships – Men's singles

John McEnroe was the defending champion but lost in the semifinals to Stefan Edberg.

Edberg won in the final 6–3, 2–6, 6–4 against Ivan Lendl.

Seeds
The top eight seeds received a bye to the second round. • # Ivan Lendl (final)

• # 🇸🇪 Stefan Edberg (champion)

• # 🇺🇸 John McEnroe (semifinals)

• # 🇫🇷 Yannick Noah (second round)

• # 🇺🇸 Brad Gilbert (quarterfinals)

• # 🇺🇸 Kevin Curren (second round)

• # 🇪🇨 Andrés Gómez (second round)

• # 🇸🇪 Mikael Pernfors (second round)

• # 🇮🇱 Amos Mansdorf (third round)

• # 🇺🇸 Dan Goldie (first round)

• # 🇸🇪 Anders Järryd (third round)

• # 🇺🇸 Jay Berger (first round)

• # 🇦🇺 John Fitzgerald (second round)

• # 🇦🇺 Wally Masur (third round)

• # 🇺🇸 Robert Seguso (second round)

• # 🇦🇺 Pat Cash (second round)