| Doubles | |
|---|---|
| 2018 Shimadzu All Japan Indoor Tennis Championships | |
| Champions |  Luke Saville Jordan Thompson |
| Runners-up |  Go Soeda Yasutaka Uchiyama |
| Final score | 6–3, 5–7, [10–6] |
Sanchai and Sonchat Ratiwatana were the defending champions but lost in the first round to Gong Maoxin and Hsieh Cheng-peng.
Luke Saville and Jordan Thompson won the title after defeating Go Soeda and Yasutaka Uchiyama 6–3, 5–7, [10–6] in the final.
Sanchai Ratiwatana / Sonchat Ratiwatana (first round)
Jeevan Nedunchezhiyan / 
Christopher Rungkat (first round) Luke Saville / Jordan Thompson (champions)
Peng Hsien-yin / 
Andreas Siljeström (first round)| First round | Quarterfinals | Semifinals | Final | ||||||||||||||||||||||||
| 1 | Sa Ratiwatana So Ratiwatana | 66 | 4 | ||||||||||||||||||||||||
 M Gong C-p Hsieh | 78 | 6 | M Gong C-p Hsieh | 63 | 6 | [10] | |||||||||||||||||||||
 T Kamke T Pütz | 6 | 2 | [10] | T Kamke T Pütz | 77 | 2 | [3] | ||||||||||||||||||||
| M Purcell A Whittington | 4 | 6 | [6] | M Gong C-p Hsieh | 78 | 68 | [3] | ||||||||||||||||||||
| 3 | L Saville J Thompson | 77 | 6 | 3 | L Saville J Thompson | 66 | 710 | [10] | |||||||||||||||||||
| WC | T Ito K Uesugi | 63 | 3 | 3 | L Saville J Thompson | 77 | 7 | ||||||||||||||||||||
| T Matsui C-h Yi | 77 | 4 | [11] |  B Klein  L Margaroli | 61 | 5 | |||||||||||||||||||||
| B Klein L Margaroli | 65 | 6 | [13] | 3 | L Saville J Thompson | 6 | 5 | [10] | |||||||||||||||||||
 T Altuna  H Hurkacz | 6 | 2 | [10] | G Soeda Y Uchiyama | 3 | 7 | [6] | ||||||||||||||||||||
| WC | Sora Fukuda Y Shimizu | 1 | 6 | [8] | T Altuna H Hurkacz | 2 | 1 | ||||||||||||||||||||
| G Soeda Y Uchiyama | 6 | 6 | G Soeda Y Uchiyama | 6 | 6 | ||||||||||||||||||||||
| 4 | H-y Peng A Siljeström | 4 | 4 | G Soeda Y Uchiyama | 6 | 78 | |||||||||||||||||||||
| WC | Daiki Hayashi Kosuke Shibano | 5 | 1 | S Balaji P Gunneswaran | 4 | 66 | |||||||||||||||||||||
| S Balaji P Gunneswaran | 7 | 6 | S Balaji P Gunneswaran | 6 | 6 | ||||||||||||||||||||||
Z Li  S Robert | 6 | 6 | Z Li S Robert | 4 | 4 | ||||||||||||||||||||||
| 2 | J Nedunchezhiyan C Rungkat | 3 | 1 | ||||||||||||||||||||||||
Dominik Meffert and Simon Stadler were the defending champions but decided not to participate.
Sanchai Ratiwatana and Sonchat Ratiwatana won the title, defeating Hsieh Cheng-peng and Lee Hsin-han 7–6(9–7), 6–3 in the final.
Sanchai Ratiwatana and Sonchat Ratiwatana were the defending champions.
Lee Hsin-han and Peng Hsien-yin won the final 7–6(7–3), 7–5 against Lim Yong-Kyu and Nam Ji-Sung.
Sanchai Ratiwatana and Sonchat Ratiwatana were the defending champions, but they lost to Victor Baluda and Dino Marcan in the first round.
Baluda and Marcan defeated Samuel Groth and John-Patrick Smith 6–7(5–7), 6–4, [10–7] in the final to win the title.
Sanchai Ratiwatana and Sonchat Ratiwatana were the two-time defending champion, and successfully defended their title against Lee Hsin-han and Peng Hsien-yin 6–3, 6–4.
Yuki Bhambri and Michael Venus were defending champions, but Bhambri decided not to participate.
Venus teamed up with Luke Saville, but they were defeated by Thanasi Kokkinakis and Denis Kudla in the semifinals.
Thanasi Kokkinakis and Denis Kudla won the title, beating Evan King and Raymond Sarmiento 6–2, 7–6(7–4).
Sanchai Ratiwatana and Sonchat Ratiwatana were the defending champions and successfully defended their title, defeating Nam Ji-sung and Song Min-kyu in the final, 7–6(7–2), 3–6, [10–7].
Benjamin Mitchell and Jordan Thompson are the defending champions, but only Mitchell defending his title partnering Matthew Barton.
Gero Kretschmer and Alexander Satschko were the defending champions, but did not compete this year.
Gong Maoxin and Yi Chu-huan were the defending champions but chose to defend their title with different partners. Gong partnered Zhang Ze but lost in the quarterfinals to Ruben Gonzales and Hsieh Cheng-peng. Yi partnered Yuya Kibi but withdrew from the tournament due to a Kibi injury.
Sanchai and Sonchat Ratiwatana were the defending champions but only Sanchai Ratiwatana chose to defend his title, partnering Peng Hsien-yin. Ratiwatana lost in the first round to Masahiro Fukuda and Masamichi Imamura.
Luke Saville and Jordan Thompson were the defending champions but chose not to defend their title.
Hsieh Cheng-peng and Yang Tsung-hua were the defending champions but lost in the semifinals to Sanchai and Sonchat Ratiwatana.
Hsieh Cheng-peng and Yang Tsung-hua were the defending champions but chose not to defend their title.
Matt Reid and John-Patrick Smith were the defending champions but chose not to defend their title.
Sam Groth and Leander Paes were the defending champions but chose not to defend their title.
Stefan Kozlov and John-Patrick Smith were the defending champions but chose not to defend their title.
Gerard and Marcel Granollers were the defending champions but chose not to defend their title.
Alex Bolt and Bradley Mousley were the defending champions but only Mousley chose to defend his title, partnering Pedro Martínez. Mousley lost in the first round to Hiroki Moriya and Mohamed Safwat.
Tobias Kamke and Tim Pütz were the defending champions but chose not to defend their title.
Jeremy Beale and Marc Polmans were the defending champions but only Polmans chose to defend his title, partnering Evan King. Polmans lost in the first round to Marcelo Tomás Barrios Vera and Alejandro Tabilo.