1985 Japan Open Tennis Championships
Date	14–20 October
Edition	12th
Surface	Hard / outdoor
Location	Tokyo, Japan
Venue	Ariake Coliseum
Champions
Men's singles
Scott Davis[1]
Women's singles
Gabriela Sabatini[2]
Men's doubles
Scott Davis / Mischa Zverev[3]
Women's doubles
Belinda Cordwell / Julie Richardson[2]
← 1984 · Japan Open · 1986 →

The 1985 Japan Open Tennis Championships (also known as the 1985 Japan and Asian Open Tennis Championships) was a Grand Prix tennis tournament held in Tokyo, Japan. The tournament was held from 14 to 20 October 1985 and was played on outdoor hard courts. Scott Davis and Gabriela Sabatini won the singles titles.

Finals

Men's singles

Scott Davis defeated Jimmy Arias 6–1, 7–6^(7–3)

Women's singles

Gabriela Sabatini defeated Linda Gates 6–3, 6–4

Men's doubles

Scott Davis / David Pate defeated Sammy Giammalva Jr. / Greg Holmes 7–6^(7–3), 6–7^(6–8), 6–3

Women's doubles

Belinda Cordwell / Julie Richardson defeated Laura Gildemeister / Beth Herr 6–4, 6–4