1999 Japan Open Tennis Championships – Women's singles

The 19999 Japan Open Tennis Championships women's singles was the women's singles event of the twenty-fifth edition of the Japan Open; a WTA Tier III tournament held in Tokyo, Japan. Ai Sugiyama was the defending champion but lost in the final 6–2, 6–2 against Amy Frazier.

	Semifinals							Final[1]
	1	Ai Sugiyama	77	6
	7	Jane Chi	65	3
								1	Ai Sugiyama	2	2
								2	Amy Frazier	6	6
	3	Corina Morariu	4	7	3
	2	Amy Frazier	6	5	6

	First round							Second round							Quarterfinals							Semifinals
	1	A Sugiyama	6	6
	LL	W Prakusya	1	3				1	A Sugiyama	6	6
		L Němečková	7	6					L Němečková	4	1
	Q	K Schlukebir	5	4											1	A Sugiyama	6	6
		S Reeves	2	2												J Lee	4	0
		J Lee	6	6					J Lee	77	6
		J Watanabe	6	6					J Watanabe	64	3
	5	K Brandi	4	2																		1	A Sugiyama	77	6
	4	K Po	7	6																		7	J Chi	65	3
		M Saeki	5	2				4	K Po	5	6	3
		S-h Park	4	2					S Kleinová	7	4	6
		S Kleinová	6	6												S Kleinová	2	0r
	Q	M Miyauchi	6	3	4										7	J Chi	6	3
		S de Beer	4	6	6				S de Beer	4	3
	Q	Y-j Cho	4	1				7	J Chi	6	6
	7	J Chi	6	6

	First round							Second round							Quarterfinals							Semifinals
	8	S-t Wang	6	6
	WC	S Obata	4	2				8	S-t Wang	6	6
		S Noorlander	4	65					Y Yoshida	1	4
		Y Yoshida	6	77											8	S-t Wang	77	3	4
		M Washington	6	6											3	C Morariu	63	6	6
	Q	H Collin	3	4					M Washington	2	0
		M Maruska	3	2				3	C Morariu	6	6
	3	C Morariu	6	6																		3	C Morariu	4	7	3
	6	M Shaughnessy	3	5																		2	A Frazier	6	5	6
		M Tu	6	7					M Tu	2	6	6
		L Wild	3	1				WC	S Asagoe	6	3	3
	WC	S Asagoe	6	6												M Tu	7	4	4
		L Andretto	4	3											2	A Frazier	5	6	6
		K-A Guse	6	6					K-A Guse	63	0
		H Inoue	0	3				2	A Frazier	77	6
	2	A Frazier	6	6

1. Wynne Prakusya

	First round							Second round							Qualifying competition
	1	Wynne Prakusya	6	6
		Keiko Tameishi	0	0
								1	Wynne Prakusya	6	79
									Yoshiko Sasano	4	67
		Yoshiko Sasano	6	7
		Miyako Ataka	1	5
															1	Wynne Prakusya	3	2
															5	Misumi Miyauchi	6	6
		Shiho Hisamatsu	2
		Akiko Gunji	1r
									Shiho Hisamatsu	7	2	1
								5	Misumi Miyauchi	5	6	6
		Sachie Umehara	6	4	1
	5	Misumi Miyauchi	2	6	6

	First round							Second round							Qualifying competition
	3	Cho Yoon-jeong	6	6
		Madoka Kuki	2	0
								3	Cho Yoon-jeong	6	6
									Maiko Inoue	2	4
		Maiko Inoue	6	6
		Kazue Takuma	2	0
															3	Cho Yoon-jeong	6	6
																Iroda Tulyaganova	4	3
		Keiko Nagatomi	6	6
	WC	Yumi Yokoi	3	2
									Keiko Nagatomi	0	4
									Iroda Tulyaganova	6	6
		Iroda Tulyaganova	6	6
	8	Adrienn Hegedűs	3	2

	First round							Second round							Qualifying competition
	7	Tomoe Hotta	6	2	63
		Akiko Kinebuchi	4	6	77
									Akiko Kinebuchi	6	6
									Hiroko Mochizuki	1	3
		Hiroko Mochizuki	1	6	6
		Riei Otakeyama	6	3	4
																Akiko Kinebuchi	5	4
															4	Katie Schlukebir	7	6
		Seiko Okamoto	4	6	6
		Benjamas Sangaram	6	4	1
									Seiko Okamoto	3	0
								4	Katie Schlukebir	6	6
		Nami Urabe	3	3
	4	Katie Schlukebir	6	6

	First round							Second round							Qualifying competition
	6	Akiko Morigami	6	6
		Keiko Ishida	0	2
								6	Akiko Morigami	6	4	1
									Hannah Collin	1	6	6
		Hannah Collin	6	6
	WC	Eri Ohmi	0	2
																Hannah Collin	6	6
															WC	Keiko Taguchi	0	2
		Chiaki Nakajima	1	79	3
	WC	Keiko Taguchi	6	67	6
								WC	Keiko Taguchi	6	2	6
								2	Kim Eun-ha	4	6	4
	WC	Kaori Goto	4	1
	2	Kim Eun-ha	6	6