# 1985 Japan Open Tennis Championships – Women's singles

Lilian Drescher was the defending champion, but lost in the semifinals to Gabriela Sabatini.
Sabatini won the title by defeating Linda Gates 6–3, 6–4 in the final.

## Seeds

* Gabriela Sabatini (champion)
* Beth Herr (second round)
* Lilian Drescher (semifinals)
* Mima Jaušovec (first round)
* Angeliki Kanellopoulou (quarterfinals)
* Laura Gildemeister (semifinals)
* Andrea Holíková (quarterfinals)
* Myriam Schropp (quarterfinals)

## Draw
### Key

* Q = Qualifier
* WC = Wild card
* LL = Lucky loser
* Alt = Alternate
* SE = Special exempt
* PR = Protected ranking
* ITF = ITF entry
* JE = Junior exempt
* w/o = Walkover
* r = Retired
* d = Defaulted
* SR = Special ranking

### Finals

| Semifinals | Semifinals | Semifinals | Semifinals | Semifinals | Final | Final | Final | Final |
| 1 | Gabriela Sabatini | 1 | 6 | 6 | | | | |
| 3 | Lilian Drescher | 6 | 3 | 3 | | | | |
| 3 | Lilian Drescher | 6 | 3 | 3 | 1 | Gabriela Sabatini | 6 | 6 |
| | | | | | | Linda Gates | 3 | 4 |
| 6 | Laura Gildemeister | 3 | 6 | 3 | | Linda Gates | 3 | 4 |
| | Linda Gates | 6 | 2 | 6 | | | | |

### Top half

| First round | First round | First round | First round | Second round | Second round | Second round | Second round | Second round | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals | Semifinals | Semifinals | Semifinals | Semifinals | Semifinals |
| 1 | G Sabatini | 6 | 6 | | | | | | | | | | | | | | |
| | E Okagawa | 1 | 1 | 1 | G Sabatini | 6 | 6 | | | | | | | | | | |
| Q | O Tsarbopoulou | 2 | 4 | | K Kinney | 0 | 0 | | | | | | | | | | |
| | K Kinney | 6 | 6 | | | | | | 1 | G Sabatini | 6 | 6 | | | | | |
| | M Yanagi | 6 | 6 | | | | | | 7 | A Holíková | 0 | 1 | | | | | |
| | P Vásquez | 1 | 1 | | ' M Yanagi | 6 | 2 | 1 | | | | | | | | | |
| | J Young | 3 | 1 | 7 | A Holíková | 3 | 6 | 6 | | | | | | | | | |
| 7 | A Holíková | 6 | 6 | | | | | | | | | | 1 | G Sabatini | 1 | 6 | 6 |
| 3 | L Drescher | 6 | 6 | | | | | | | | | | 3 | L Drescher | 6 | 3 | 3 |
| | C Bartos-Cserepy | 3 | 2 | 3 | L Drescher | 6 | 6 | | | | | | | | | | |
| | Rie Nakazawa | 4 | 2 | | A Kijimuta | 3 | 0 | | | | | | | | | | |
| | A Kijimuta | 6 | 6 | | | | | | 3 | L Drescher | 6 | 6 | | | | | |
| | N Dias | 1 | 1 | | | | | | 5 | A Kanellopoulou | 3 | 1 | | | | | |
| | M Paz | 6 | 6 | | M Paz | 0 | 4 | | | | | | | | | | |
| | P Medrado | 5 | 6 | 5 | A Kanellopoulou | 6 | 6 | | | | | | | | | | |
| 5 | A Kanellopoulou | 7 | 7 | | | | | | | | | | | | | | |

### Bottom half

| First round | First round | First round | First round | First round | Second round | Second round | Second round | Second round | Second round | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals | Semifinals | Semifinals | Semifinals | Semifinals | Semifinals |
| 6 | L Gildemeister | 6 | 7 | | | | | | | | | | | | | | | | |
| Q | D Farrell | 2 | 6 | | 6 | L Gildemeister | 6 | 6 | 7 | | | | | | | | | | |
| | J Thompson | 6 | 6 | | | J Thompson | 7 | 3 | 6 | | | | | | | | | | |
| Q | J Louis | 3 | 4 | | | | | | | 6 | L Gildemeister | 6 | 4 | 6 | | | | | |
| | H Ludloff | 2 | 3 | | | | | | | | A Holton | 3 | 6 | 0 | | | | | |
| | B Cordwell | 6 | 6 | | | B Cordwell | 4 | 4 | | | | | | | | | | | |
| | A Holton | 2 | 7 | 6 | | A Holton | 6 | 6 | | | | | | | | | | | |
| 4 | M Jaušovec | 6 | 5 | 3 | | | | | | | | | | | 6 | L Gildemeister | 3 | 6 | 3 |
| 8 | M Schropp | 1 | 6 | 6 | | | | | | | | | | | | L Gates | 6 | 2 | 6 |
| | Y Koizumi | 6 | 3 | 2 | 8 | M Schropp | 7 | 7 | | | | | | | | | | | |
| | E Inoue | 6 | 6 | | | E Inoue | 5 | 5 | | | | | | | | | | | |
| | A Villagrán | 1 | 2 | | | | | | | 8 | M Schropp | 4 | 4 | | | | | | |
| | L Gates | 6 | 3 | 6 | | | | | | | L Gates | 6 | 6 | | | | | | |
| | M Lindström | 1 | 6 | 4 | | L Gates | 6 | 6 | | | | | | | | | | | |
| | S Foltz | 6 | 4 | 3 | 2 | B Herr | 3 | 1 | | | | | | | | | | | |
| 2 | B Herr | 4 | 6 | 6 | | | | | | | | | | | | | | | |