# 1981 Japan Open Tennis Championships – Men's singles

Ivan Lendl was the defending champion, but he chose to compete at Vienna during the same week, winning that tournament.
Balázs Taróczy won the Tokyo title by defeating Eliot Teltscher 6–3, 1–6, 7–6 in the final.

## Seeds

* Eliot Teltscher (final)
* Balázs Taróczy (champion)
* Wojciech Fibak (quarterfinals)
* Mel Purcell (quarterfinals)
* Ricardo Cano (quarterfinals)
* Peter Rennert (first round)
* Heinz Günthardt (third round)
* Terry Moor (quarterfinals)
* Ramesh Krishnan (first round)
* Tim Gullikson (third round)
* Pat DuPré (semifinals)
* Buster Mottram (third round)
* Martin Davis (third round)
* Larry Stefanki (third round)
* Scott McCain (second round)
* James Delaney (third round)

## 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

| Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals | Semifinals | Semifinals | Semifinals | Semifinals | Semifinals | Final | Final | Final | Final | Final |
| 1 | Eliot Teltscher | 6 | 6 | | | | | | | | | | |
| 8 | Terry Moor | 1 | 4 | | | | | | | | | | |
| 8 | Terry Moor | 1 | 4 | 1 | Eliot Teltscher | 6 | 6 | | | | | | |
| | | | | | Van Winitsky | 4 | 4 | | | | | | |
| 4 | Mel Purcell | 6 | 5 | | Van Winitsky | 4 | 4 | | | | | | |
| | Van Winitsky | 7 | 7 | | | | | | | | | | |
| | Van Winitsky | 7 | 7 | | | | | | 1 | Eliot Teltscher | 3 | 6 | 6 |
| | | | | | | | | | 2 | Balázs Taróczy | 6 | 1 | 7 |
| 11 | Pat DuPré | 7 | 6 | | | | | | | | | | | 2 | Balázs Taróczy | 6 | 1 | 7 |
| 3 | Wojciech Fibak | 6 | 4 | | | | | | | | | | |
| 3 | Wojciech Fibak | 6 | 4 | 11 | Pat DuPré | 3 | 6 | 2 | | | | | |
| | | | | 2 | Balázs Taróczy | 6 | 4 | 6 | | | | | |
| 5 | Ricardo Cano | 3 | 1 | 2 | Balázs Taróczy | 6 | 4 | 6 | | | | | |
| 2 | Balázs Taróczy | 6 | 6 | | | | | | | | | | |

### Top half
#### Section 1

| First round | First round | First round | First round | First round | Second round | Second round | Second round | Second round | Third round | Third round | Third round | Third round | Third round | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals |
| 1 | E Teltscher | 6 | 6 | | | | | | | | | | | | | | |
| | Yoshito Nakamura | 0 | 1 | | 1 | E Teltscher | 6 | 6 | | | | | | | | | |
| | T Kuramitsu | 2 | 2 | | | T Fukui | 1 | 2 | | | | | | | | | |
| | T Fukui | 6 | 6 | | | | | | 1 | E Teltscher | 5 | 7 | 6 | | | | |
| | Toshio Iwasawa | 3 | 1 | | | | | | 12 | B Mottram | 7 | 5 | 3 | | | | |
| | C Dunk | 6 | 6 | | | C Dunk | 2 | 0 | | | | | | | | | |
| Q | S Kato | 5 | 0 | | 12 | B Mottram | 6 | 6 | | | | | | | | | |
| 12 | B Mottram | 7 | 6 | | | | | | | | | | | 1 | E Teltscher | 6 | 6 |
| 14 | L Stefanki | 6 | 6 | | | | | | | | | | | 8 | T Moor | 1 | 4 |
| | Nobuya Tamura | 1 | 1 | | 14 | L Stefanki | 6 | 6 | | | | | | | | | |
| Q | Haruhiko Matsunaga | 7 | 4 | 1 | Q | T Kanai | 0 | 3 | | | | | | | | | |
| Q | Taisen Kanai | 5 | 6 | 6 | | | | | 14 | L Stefanki | 5 | 4 | | | | | |
| | Bob Weise | 6 | 6 | | | | | | 8 | T Moor | 7 | 6 | | | | | |
| | Tokio Nishiwaki | 4 | 0 | | | B Weise | 3 | 4 | | | | | | | | | |
| | Yoshiya Hamano | 1 | 2 | | 8 | T Moor | 6 | 6 | | | | | | | | | |
| 8 | T Moor | 6 | 6 | | | | | | | | | | | | | | |

#### Section 2

| First round | First round | First round | First round | First round | Second round | Second round | Second round | Second round | Second round | Third round | Third round | Third round | Third round | Third round | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals |
| 4 | M Purcell | 6 | 6 | | | | | | | | | | | | | | | |
| | Bill Shivar | 2 | 3 | | 4 | M Purcell | 6 | 6 | | | | | | | | | | |
| | Hirato Shibata | 4 | 6 | 6 | | H Shibata | 2 | 2 | | | | | | | | | | |
| | Yukihiko Murata | 6 | 1 | 3 | | | | | | 4 | M Purcell | 6 | 6 | 6 | | | | |
| | Shinichi Nishino | 5 | 2 | | | | | | | 10 | T Gullikson | 3 | 7 | 3 | | | | |
| Q | B Webb | 7 | 6 | | Q | B Webb | 1 | 2 | | | | | | | | | | |
| | Naomi Uemura | 2 | 2 | | 10 | T Gullikson | 6 | 6 | | | | | | | | | | |
| 10 | T Gullikson | 6 | 6 | | | | | | | | | | | | 4 | M Purcell | 6 | 5 |
| 16 | J Delaney | 7 | 7 | | | | | | | | | | | | | V Winitsky | 7 | 7 |
| | L Bourne | 5 | 5 | | 16 | J Delaney | 6 | 6 | 6 | | | | | | | | | |
| Q | Noriyuki Washida | 4 | 3 | | | K Tsukamoto | 3 | 7 | 4 | | | | | | | | | |
| | Kunio Tsukamoto | 6 | 6 | | | | | | | 16 | J Delaney | 7 | 4 | 4 | | | | |
| | M Estep | 7 | 4 | 0 | | | | | | | V Winitsky | 6 | 6 | 6 | | | | |
| | V Winitsky | 6 | 6 | 6 | | V Winitsky | 6 | 6 | | | | | | | | | | |
| | D Dowlen | 7 | 4 | 6 | | D Dowlen | 0 | 1 | | | | | | | | | | |
| 6 | P Rennert | 6 | 6 | 1 | | | | | | | | | | | | | | |

### Bottom half
#### Section 3

| First round | First round | First round | First round | First round | Second round | Second round | Second round | Second round | Second round | Third round | Third round | Third round | Third round | Third round | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals |
| 7 | H Günthardt | 6 | 7 | | | | | | | | | | | | | | | |
| | Weller Evans | 2 | 5 | | 7 | H Günthardt | 6 | 2 | 6 | | | | | | | | | |
| | S Sakamoto | 7 | 6 | | | S Sakamoto | 4 | 6 | 1 | | | | | | | | | |
| | Toyokazu Tomogane | 5 | 1 | | | | | | | 7 | H Günthardt | 5 | 2 | | | | | |
| | H Shirato | 7 | 6 | | | | | | | 11 | P DuPré | 7 | 6 | | | | | |
| | K Tanabe | 5 | 1 | | | H Shirato | 1 | 2 | | | | | | | | | | |
| | Akinori Naguro | 1 | 3 | | 11 | P DuPré | 6 | 6 | | | | | | | | | | |
| 11 | P DuPré | 6 | 6 | | | | | | | | | | | | 11 | P DuPré | 7 | 6 |
| 13 | M Davis | 5 | 6 | 7 | | | | | | | | | | | 3 | W Fibak | 6 | 4 |
| | S Menon | 7 | 3 | 6 | 13 | M Davis | 7 | 6 | | | | | | | | | | |
| | I Dupasquier | 6 | 6 | | | I Dupasquier | 6 | 1 | | | | | | | | | | |
| | Wataru Fujii | 0 | 1 | | | | | | | 13 | M Davis | 6 | 4 | 0 | | | | |
| | E Takeuchi | 6 | 2 | 6 | | | | | | 3 | W Fibak | 3 | 6 | 6 | | | | |
| | Etsuo Uchiyama | 2 | 6 | 4 | | E Takeuchi | 2 | 5 | | | | | | | | | | |
| Q | Takao Yamamoto | 3 | 3 | | 3 | W Fibak | 6 | 7 | | | | | | | | | | |
| 3 | W Fibak | 6 | 6 | | | | | | | | | | | | | | | |

#### Section 4

| First round | First round | First round | First round | First round | Second round | Second round | Second round | Second round | Second round | Third round | Third round | Third round | Third round | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals |
| 5 | R Cano | 6 | 7 | | | | | | | | | | | | | | |
| | Kiyoshi Miyanami | 3 | 5 | | 5 | R Cano | 5 | 6 | 6 | | | | | | | | |
| | J Bailey | 6 | 6 | | | J Bailey | 7 | 3 | 2 | | | | | | | | |
| | K Hirai | 4 | 2 | | | | | | | 5 | R Cano | 6 | 6 | | | | |
| | R Van't Hof | 6 | 6 | | | | | | | | R Van't Hof | 3 | 1 | | | | |
| | E Wilborts | 2 | 1 | | | R Van't Hof | 6 | 1 | 6 | | | | | | | | |
| | Nial Brash | 0 | 3 | | 15 | S McCain | 2 | 6 | 3 | | | | | | | | |
| 15 | S McCain | 6 | 6 | | | | | | | | | | | 5 | R Cano | 3 | 1 |
| 9 | R Krishnan | 2 | 6 | | | | | | | | | | | 2 | B Taróczy | 6 | 6 |
| | J Kuki | 6 | 7 | | | J Kuki | 6 | 6 | | | | | | | | | |
| | S Nishio | 6 | 6 | | | S Nishio | 3 | 4 | | | | | | | | | |
| | T Yonezawa | 3 | 1 | | | | | | | | J Kuki | 1 | 2 | | | | |
| | D Gitlin | 6 | 3 | 7 | | | | | | 2 | B Taróczy | 6 | 6 | | | | |
| | B Sison | 1 | 6 | 5 | | D Gitlin | 4 | 2 | | | | | | | | | |
| Q | S Shiraishi | 0 | 1 | | 2 | B Taróczy | 6 | 6 | | | | | | | | | |
| 2 | B Taróczy | 6 | 6 | | | | | | | | | | | | | | |