The 1998 Mercedes-Benz Cup was a men's tennis tournament played on hardcourt in Los Angeles, United States that was part of the International Series of the 1998 ATP Tour. It was the seventy-first edition of the tournament and was held from July 27 through August 2, 1998.

Champion seeds are indicated in bold text while text in italics indicates the round in which those seeds were eliminated.

	Semifinals							Final[1]
	WC	Justin Gimelstob	0	62
	5	Andre Agassi	6	7
								5	Andre Agassi	6	6
								2	Tim Henman	4	4
		Guillaume Raoux	5	3
	2	Tim Henman	7	6

	First round							Second round							Quarterfinals							Semifinals
	1	P Rafter	6	6
		R Delgado	3	2				1	P Rafter	6	5	6
		M Damm	2	7	6				M Damm	3	7	1
		W Black	6	5	0										1	P Rafter	4	3
	WC	J Gimelstob	6	6											WC	J Gimelstob	6	6
		D Vacek	4	0				WC	J Gimelstob	6	3
	8	V Spadea	2	6	6			8	V Spadea	3	0	R
	Q	M Ondruska	6	3	3																	WC	J Gimelstob	0	62
	LL	S Stolle	6	6																		5	A Agassi	6	7
	Q	T Dent	3	2				LL	S Stolle	6	7
		A Ilie	6	6					A Ilie	3	66
	PR	MV Washington	4	1											LL	S Stolle	62	2
		J-M Gambill	6	6											5	A Agassi	7	6
		S Campbell	4	4					J-M Gambill	4	4
	5	A Agassi	6	6				5	A Agassi	6	6
	WC	B Bryan	4	3

	First round							Second round							Quarterfinals							Semifinals
		S Sargsian	6	6
	6	W Ferreira	1	2					S Sargsian	3	6	2
	Q	M Joyce	7	2	7				M Joyce	6	4	6
		M Tebbutt	5	6	5											M Joyce	7	4	5
		K Carlsen	7	6												G Raoux	67	6	7
	LL	Ó Burrieza	5	4					K Carlsen	67	7	63
		G Raoux	6	6					G Raoux	7	61	7
	3	G Ivanišević	4	4																			G Raoux	5	3
	7	B Black	6	7																		2	T Henman	7	6
		S Schalken	4	68				7	B Black	6	6
		G Pozzi	6	6					G Pozzi	3	2
		G Cañas	2	4											7	B Black	7	1	4
		J Tarango	6	6											2	T Henman	5	6	6
	Q	A Hernández	2	2					J Tarango	66	5
	2	T Henman	6	6				2	T Henman	7	7
		G Stafford	3	0