Men's singles
2019 Keio Challenger
Champion	Kwon Soon-woo
Runner-up	Oscar Otte
Score	7–6(7–4), 6–3

Yasutaka Uchiyama was the defending champion but chose not to defend his title.

Kwon Soon-woo won the title after defeating Oscar Otte 7–6^(7–4), 6–3 in the final.

Seeds

All seeds receive a bye into the second round.

Draw

Finals

	Quarterfinals							Semifinals							Final
		Lee Duck-hee	1	0
	11	Kwon Soon-woo	6	6
								11	Kwon Soon-woo	6	6
								3	Yūichi Sugita	3	2
	3	Yūichi Sugita	2	6	7
	8	Dudi Sela	6	4	5
															11	Kwon Soon-woo	77	6
															2	Oscar Otte	64	3
		Yang Tsung-hua	5	64
		Andrew Harris	7	77
									Andrew Harris	3	4
								2	Oscar Otte	6	6
	10	Gianluca Mager	2	4
	2	Oscar Otte	6	6

Top half

Section 1

	First round							Second round							Third round							Quarterfinals
								1	T Ito	6	7
		Y Takahashi	5	7	2			ITF	M Echargui	0	5
	ITF	M Echargui	7	5	6										1	T Ito	3	6	67
		D-h Lee	6	6												D-h Lee	6	4	79
		Xia Zihao	0	3					D-h Lee	6	6
								16	E Couacaud	0	2
																							D-h Lee	1	0
																						11	S-w Kwon	6	6
								11	S-w Kwon	6	6
		Renta Tokuda	5	2				WC	M Imamura	2	2
	WC	M Imamura	7	6											11	S-w Kwon	6	6
	WC	S Hazawa	62	4											5	M Moraing	2	4
		TK Wang	77	6					TK Wang	68	2
								5	M Moraing	710	6

Section 2

	First round							Second round							Third round							Quarterfinals
								3	Y Sugita	2	6	7
		B Ellis	6	5	5			PR	D Nguyen	6	4	5
	PR	D Nguyen	3	7	7										3	Y Sugita	6	6
		G Oliveira	3	65											14	F Peliwo	4	2
	ITF	I Gakhov	6	77				ITF	I Gakhov	2	4
								14	F Peliwo	6	6
																						3	Y Sugita	2	6	7
																						8	D Sela	6	4	5
								9	B Rola	77	6
		K Uchida	6	6					K Uchida	63	4
		Roy Smith	3	3											9	B Rola	3	1
		L Saville	2	6	6										8	D Sela	6	6
	WC	K Uesugi	6	4	2				L Saville	2	0
								8	D Sela	6	6

Bottom half

Section 3

	First round							Second round							Third round							Quarterfinals
								6	J Rodionov	79	0	6
	LL	Shintaro Imai	2	3				ITF	D Pérez Sanz	67	6	4
	ITF	D Pérez Sanz	6	6											6	J Rodionov	4	4
		Y-s Chung	4	3												T-h Yang	6	6
		T-h Yang	6	6					T-h Yang	6	6
								12	P Cachin	4	4
																							T-h Yang	5	64
																							A Harris	7	77
								13	G Clezar	6	2	64
		D Wu	4	6	2				G Elias	0	6	77
		G Elias	6	3	6											G Elias	4	7	4
		A Harris	6	6												A Harris	6	5	6
	WC	Sung Yo-han	1	2					A Harris	6	6
								4	H Moriya	3	3

Section 4

	First round							Second round							Third round							Quarterfinals
								7	G Soeda	6	6
	Q	Kim Cheong-eui	6	6				Q	C-e Kim	1	4
	WC	Naoto Kai	1	3											7	G Soeda	6	5	5
	Q	C-h Tseng	6	3	6										10	G Mager	3	7	7
	ITF	S Mansouri	4	6	3			Q	C-h Tseng	63	65
								10	G Mager	77	77
																						10	G Mager	2	4
																						2	O Otte	6	6
								15	V Troicki	5	65
		M Purcell	6	6					M Purcell	7	77
		K King	2	2												M Purcell	6	5	4
		Y Bai	6	0	7										2	O Otte	1	7	6
		Makoto Ochi	2	6	5				Y Bai	3	2
								2	O Otte	6	6

References

• Main Draw
• Qualifying Draw