Singles
2011 Kōfu International Open
Champion	Chang Kai-chen
Runner-up	Mandy Minella
Score	6–4, 1–6, 6–4

Sachie Ishizu was the defending champion, but lost to Tamarine Tanasugarn in the second round.
Chang Kai-chen won the title, defeating Mandy Minella 6–4, 1–6, 6–4 in the final.

Seeds

Main draw

Finals

	Semifinals							Final
	1	Tamarine Tanasugarn	3	2
	5	Mandy Minella	6	6
								5	Mandy Minella	4	6	4
								4	Chang Kai-chen	6	1	6
	4	Chang Kai-chen	6	4	6
	2	Erika Sema	4	6	4

Top half

	First round							Second round							Quarterfinals							Semifinals
	1	T Tanasugarn	6	6
	WC	R Ozaki	3	4				1	T Tanasugarn	6	6
		S Ishizu	6	6					S Ishizu	1	3
	Q	Y Miyazaki	2	4											1	T Tanasugarn	6	6
		C Ogi	1	2												A Omae	3	4
		A Omae	6	6					A Omae	7	66	77
	WC	R Sawayanagi	1	6	6			WC	R Sawayanagi	5	78	62
	8	A Nakamura	6	4	3																	1	T Tanasugarn	3	2
	3	N Lertcheewakarn	6	0	2																	5	M Minella	6	6
		C Takayama	4	6	6				C Takayama	65	6	6
		E Takao	77	4	2				M Eguchi	77	1	2
		M Eguchi	62	6	6											C Takayama	0	6	2
		H Watanabe	710	3	64										5	M Minella	6	4	6
	Q	Y Sakai	68	6	77			Q	Y Sakai	1	0
		K Hisami	1	2				5	M Minella	6	6
	5	M Minella	6	6

Bottom half

	First round							Second round							Quarterfinals							Semifinals
	7	J Namigata	6	6
	WC	M Minokoshi	0	1				7	J Namigata	6	5	7
		N Hamamura	77	1	1				W-h Hsu	2	7	5
		W-h Hsu	65	6	6										7	J Namigata	6	3	4
		A Oka	6	5	5										4	K-c Chang	2	6	6
		A Yonemura	2	7	7				A Yonemura	3	1
		C-w Chan	3	2				4	K-c Chang	6	6
	4	K-c Chang	6	6																		4	K-c Chang	6	4	6
	6	Y Sema	6	6																		2	E Sema	4	6	4
		Y Koshino	4	4				6	Y Sema	6	6
	WC	Y Tanaka	4	6	6			WC	Y Tanaka	1	1
	Q	M Ayukawa	6	0	2										6	Y Sema	0	6	3
	Q	A Yamasoto	5	6	3										2	E Sema	6	4	6
		R Tezuka	7	4	6				R Tezuka	2	0
		M Tanaka	0	2				2	E Sema	6	6
	2	E Sema	6	6

References

• Main Draw
• Qualifying Draw