Men's singles
2017 Keio Challenger
Final
Champion	Yūichi Sugita
Runner-up	Kwon Soon-woo
Score	6–4, 2–6, 7–6(7–2)
Events
Singles men women Doubles men women
← 2015 · Keio Challenger · 2018 →

Taro Daniel was the defending champion but chose not to defend his title.

Yūichi Sugita won the title after defeating Kwon Soon-woo 6–4, 2–6, 7–6^(7–2) in the final.

	Semifinals							Final
	1	Yūichi Sugita	4	78	6
	Q	Blake Mott	6	66	2
								1	Yūichi Sugita	6	2	77
								Q	Kwon Soon-woo	4	6	62
		Tatsuma Ito	4	4
	Q	Kwon Soon-woo	6	6

	First round							Second round							Quarterfinals							Semifinals
	1	Y Sugita	6	6
		A Velotti	4	4				1	Y Sugita	6	6
		C O'Connell	1	77	3				D Wu	4	4
		D Wu	6	61	6										1	Y Sugita	6	6
		B Kavčič	4	6	6										7	Z Zhang	2	1
		M Matosevic	6	0	4				B Kavčič	4	65
	WC	Yo Watanuki	3	0				7	Z Zhang	6	77
	7	Z Zhang	6	6																		1	Y Sugita	4	78	6
	3	D-h Lee	5	78	1																	Q	B Mott	6	66	2
		M Tepavac	7	66	6				M Tepavac	3	4
		F Škugor	3	5				Q	B Klein	6	6
	Q	B Klein	6	7											Q	B Klein	4	1
		M Polmans	4	7	6										Q	B Mott	6	6
	PR	C-M Stebe	6	5	0				M Polmans	4	2
	Q	B Mott	6	6				Q	B Mott	6	6
	5	G Žemlja	2	3

	First round							Second round							Quarterfinals							Semifinals
	6	R Bemelmans	6	6
	SE	L Harris	3	4				6	R Bemelmans	4	6	3
		Y Uchiyama	4	6	3			WC	K Uesugi	6	3	6
	WC	K Uesugi	6	1	6										WC	K Uesugi	77	2	62
		J De Loore	63	1												T Ito	63	6	77
		T Ito	77	6					T Ito	6	6
		H Moriya	4	4				4	G Soeda	4	1
	4	G Soeda	6	6																			T Ito	4	4
	8	A Whittington	65	6	6																	Q	S-w Kwon	6	6
	WC	Sora Fukuda	77	4	2			8	A Whittington	6	77
	Q	T Niki	6	6				Q	T Niki	4	65
	WC	Masato Shiga	1	1											8	A Whittington	4	4
	Q	S-w Kwon	6	77											Q	S-w Kwon	6	6
		J Jung	3	62				Q	S-w Kwon	77	6
		Z Li	6	77					Z Li	65	3
	2	H Laaksonen	3	65

• Main Draw
• Qualifying Draw