Virginia Ruzici defeated defending champion Mima Jaušovec in the final, 6–2, 6–2 to win the women's singles tennis title at the 1978 French Open.^[1] It was her first and only major title.

The seeded players are listed below. Virginia Ruzici is the champion; others show the round in which they were eliminated.

• Q = Qualifier
• WC = Wild card
• LL = Lucky loser
• r = Retired

	Quarterfinals							Semifinals							Finals
	1	Mima Jaušovec	6	6
	5	Kathy May	4	2
								1	Mima Jaušovec	6	6
								3	Regina Maršíková	3	4
	3	Regina Maršíková	6	6
	Q	Helga Masthoff	3	3
															1	Mima Jaušovec	2	2
															2	Virginia Ruzici	6	6
	Q	Mirka Bendlová	3	3
		Brigitte Simon	6	6
									Brigitte Simon	3	0
								2	Virginia Ruzici	6	6
	13	Fiorella Bonicelli	7	4	6
	2	Virginia Ruzici	6	6	8

	First round							Second round							Third round							Quarterfinals
	1	Jaušovec	6	6
		Walsh	1	3				1	Jaušovec	6	6
		Nagelsen	6	7					Nagelsen	4	2
		Hanika	4	5											1	Jaušovec	6	6
	Q	Bowrey	7	6											Q	Bowrey	1	3
		Coles	5	4				Q	Bowrey	7	6
	12	Tyler	6	6				12	Tyler	5	4
		Gerulaitis	2	2																		1	Jaušovec	6	6
	9	Tomanová	6	7																		5	May	4	2
	Q	Gregory	1	5				9	Tomanová	3	7	4
		Strachoňová	7	6					Strachoňová	6	6	6
		Giscafré	6	1												Strachoňová	1	0
		Sparre-Viragh	6	6											5	May	6	6
		Wikstedt	3	4					Sparre-Viragh	6	2	6
	5	May	6	6				5	May	4	6	8
		Ganz	1	2

	First round							Second round							Third round							Quarterfinals
	3	Maršíková	7	6
		Whytcross	5	1				3	Maršíková	6	6
		Desfor	6	6	6				Desfor	0	4
		Anliot	7	3	3										3	Maršíková	6	6
	Q	Budařová	6	6											14	Simionescu	1	4
		Fayter	1	3				Q	Budařová	7	5	3
	14	Simionescu	6	6				14	Simionescu	6	7	6
		Evers	4	2																		3	Maršíková	6	6
	15	Louie	6	6																		Q	Masthoff	3	3
		Harris	2	3				15	Louie	6	4	2
	Q	Masthoff	4	6	6			Q	Masthoff	3	6	6
	Q	Madruga	6	0	4										Q	Masthoff	7	6
		Hunt	6	6												Hunt	6	4
		Ornstein	2	3					Hunt	6	5	6
	7	Ebbinghaus	6	2	6			7	Ebbinghaus	4	7	0
		O'Neil	2	6	2

	First round							Second round							Third round							Quarterfinals
	Q	Bendlová	6	2	6
	8	Du Pont	4	6	3			Q	Bendlová	1	6	6
		Rual	6	6					Rual	6	2	3
		Klein	1	2											Q	Bendlová	6	6
		Medrado	6	2	6											Medrado	3	4
		Riedel	4	6	3				Medrado	6	6
	11	Evert	6	6	6			11	Evert	1	2
		Simmonds	7	3	2																	Q	Bendlová	3	3
		Simon	7	6																			Simon	6	6
	10	Mihai	5	2					Simon	6	6
	Q	Tobin	6	6				Q	Tobin	1	1
		Stratton	1	2												Simon	6	6
		González	6	6												González	4	3
		Bohm	4	3					González	6	4	6
	4	Richey	6	6				4	Richey	4	6	3
		Bostrom	2	2

	First round							Second round							Third round							Quarterfinals
		Teeguarden	7	2	7
	6	Newberry	5	6	5				Teeguarden	6	6
		Eisterlehner	4	6	6				Eisterlehner	1	4
		Smith	6	3	2											Teeguarden	3	7	4
	Q	Mandlíková	6	6											13	Bonicelli	6	6	6
		Pinterová	2	1				Q	Mandlíková	2	5
	13	Bonicelli	6	6				13	Bonicelli	6	7
		Fuchs	4	1																		13	Bonicelli	7	4	6
		Thibault	6	6																		2	Ruzici	6	6	8
	16	Stoll	3	4					Thibault	7	6
		Latham	4	6	6				Latham	5	3
		Lovera	6	4	4											Thibault	3	2
		Ekblom	6	7											2	Ruzici	6	6
		Doerner	2	5					Ekblom	1	3
	2	Ruzici	6	6				2	Ruzici	6	6
		Blackwood	4	0

• 1978 French Open – Women's draws and results at the International Tennis Federation