Men's doubles
2017 Keio Challenger
Champions	Marin Draganja Tomislav Draganja
Runners-up	Joris De Loore Luke Saville
Score	4–6, 6–3, [10–4]

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.

Marin and Tomislav Draganja won the title after defeating Joris De Loore and Luke Saville 4–6, 6–3, [10–4] in the final.

Seeds

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

	First round							Quarterfinals							Semifinals							Final
	1	M Gong Z Zhang	6	6
	WC	Nasa Hatakeyama Kaito Itsusaki	1	3				1	M Gong Z Zhang	7	6
		R Gonzales T Matsui	65	6	[7]				C-p Hsieh H Moriya	5	2
		C-p Hsieh H Moriya	77	4	[10]										1	M Gong Z Zhang	3	64
	4	D Wu C-h Yi	6	4	[9]											M Draganja T Draganja	6	77
		M Draganja T Draganja	4	6	[11]				M Draganja T Draganja	77	7
		B Rola G Žemlja	62	6	[7]			WC	Y Mochizuki H Yata	62	5
	WC	Yuki Mochizuki Hiroki Yata	77	3	[10]																		M Draganja T Draganja	4	6	[10]
	Q	Han Sung-min K Uesugi	4	2																			J De Loore L Saville	6	3	[4]
		J De Loore L Saville	6	6					J De Loore L Saville	77	6
		B Klein Y Sugita	3	3				3	A Bolt A Whittington	65	3
	3	A Bolt A Whittington	6	6												J De Loore L Saville	6	6
		D-h Lee R Roelofse	3	1												S de Waard B McLachlan	4	2
		S de Waard B McLachlan	6	6					S de Waard B McLachlan	6	6
	WC	Masahiro Fukuda M Imamura	2	710	[10]			WC	M Fukuda M Imamura	2	1
	2	H-y Peng Sa Ratiwatana	6	68	[5]

References

• Main Draw
• Qualifying Draw