| Champ: |  Juan Martín del Potro |
| Runner: |  Milos Raonic |
| Score: | 7–6(7–5), 7–5 |
| Type: | singles doubles |
| Draw: | 32 (4 / 4) |
| Seeds: | 8 |
| Before Name: | Rakuten Japan Open Tennis Championships – Singles |
| After Name: | Rakuten Japan Open Tennis Championships – Singles |
| Main Name: | Japan Open (tennis) Japan Open |
See main article: 2013 Rakuten Japan Open Tennis Championships.
Kei Nishikori was the defending champion, but lost in the quarter-finals to Nicolás Almagro.
First-seeded Juan Martín del Potro won the title, defeating Milos Raonic in the final, 7–6(7–5), 7–5.