Chris O'Neil defeated Betsy Nagelsen in the final, 6–3, 7–6^(7–3) to win the women's singles tennis title at the 1978 Australian Open. It was her first and only major singles title. O'Neil did not lose a set during the tournament.

Evonne Goolagong was the reigning champion, but she did not compete this year due to injury.

The seeded players are listed below. Chris O'Neil is the champion; others show the round in which they were eliminated.

1. Sue Barker (quarterfinals)
2. Renáta Tomanová (quarterfinals)
3. Beth Norton (second round)
4. Amanda Tobin (first round)
5. Renee Blount (second round)
6. Cynthia Doerner (first round)
7. Withdrawn
8. Betsy Nagelsen (finalist)

	Quarterfinals							Semifinals							Finals
	1	Sue Barker	2	6
		Dianne Evers	6	7
									Dianne Evers	0	3
									Chris O'Neil	6	6
		Chris O'Neil	7	6
	Q	Dorte Ekner	5	1
																Chris O'Neil	6	7
															8	Betsy Nagelsen	3	6
		Mary Sawyer	4	3
	Q	Christine Matison	6	6
								Q	Christine Matison	5	4
								8	Betsy Nagelsen	7	6
	8	Betsy Nagelsen	6	6
	2	Renáta Tomanová	4	4

	First round							Second round							Quarterfinals							Semifinals
	1	S Barker	6	6
	Q	K Gulley	0	2				1	S Barker	6	7
		M Gurdal	6	6					M Gurdal	2	5
		W Gilchrist	2	1											1	S Barker	2	6
		D Evers	6	3	6											D Evers	6	7
		K Ruddell	2	6	1				D Evers	6	6
		E Ekblom	4	3				5	R Blount	4	3
	5	R Blount	6	6																			D Evers	0	3
	3	B Norton	6	6																			C O'Neil	6	6
	Q	J Walker	1	4				3	B Norton	4	3
		C O'Neil	6	6					C O'Neil	6	6
		L Harrison	2	4												C O'Neil	7	6
		H Eisterlehner	6	6											Q	D Ekner	5	1
		N Sato	2	4					H Eisterlehner	6	1	2
	Q	D Ekner	6	6				Q	D Ekner	4	6	6
	6	C Doerner	4	3

	First round							Second round							Quarterfinals							Semifinals
	LL	B Hermansen	2	5
		P Bostrom	6	7					P Bostrom	6	3	5
		M Sawyer	6	7					M Sawyer	4	6	7
		K Hallam	2	5												M Sawyer	6	6
		K Sands	6	6											Q	C Matison	4	3
		S Saliba	2	0					K Sands	6	2	4
	Q	C Matison	6	6				Q	C Matison	1	6	6
	4	A Tobin	1	3																		Q	C Matison	5	4
	8	B Nagelsen	6	6																		8	B Nagelsen	7	6
		S Simmonds	1	3				8	B Nagelsen	6	6
		N Bohm	6	6					N Bohm	3	4
		J Chaloner	4	2											8	B Nagelsen	6	6
		N Gregory	6	1	6										2	R Tomanová	4	4
		K Pratt	3	6	3				N Gregory	2	5
		P Whytcross	4	1				2	R Tomanová	6	7
	2	R Tomanová	6	6

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