The 1999 FIA GT Monza 500 km was the opening round the 1999 FIA GT Championship season. It took place at the Autodromo Nazionale Monza, Italy, on April 11, 1999. This event was shared with a Sports Racing World Cup round.

Cars failing to complete 70% of winner's distance are marked as Not Classified (NC).

Pos	No	Team	Drivers	Chassis	Tyre	Laps
				Engine
1	1	Chrysler Viper Team Oreca	Olivier Beretta Karl Wendlinger	Chrysler Viper GTS-R	M	86
				Chrysler 8.0L V10
2	2	Chrysler Viper Team Oreca	Jean-Philippe Belloc David Donohue	Chrysler Viper GTS-R	M	86
				Chrysler 8.0L V10
3	15	Freisinger Motorsport	Michel Ligonnet Wolfgang Kaufmann	Porsche 911 GT2	D	85
				Porsche 3.6L Turbo Flat-6
4	19	Chamberlain Motorsport	Christian Vann Christian Gläsel	Chrysler Viper GTS-R	M	85
				Chrysler 8.0L V10
5	33	GLPK Racing	Vincent Vosse Didier Defourny	Chrysler Viper GTS-R	D	85
				Chrysler 8.0L V10
6	21	Paul Belmondo Racing	Paul Belmondo Claude Yves-Gosselin	Chrysler Viper GTS-R	D	84
				Chrysler 8.0L V10
7	8	Haberthur Racing	Luca Cappellari Filippo Salvarni Michel Neugarten	Porsche 911 GT2	D	83
				Porsche 3.6L Turbo Flat-6
8	3	Roock Racing	Claudia Hürtgen Stéphane Ortelli	Porsche 911 GT2	Y	83
				Porsche 3.6L Turbo Flat-6
9	29	Autorlando	Marco Spinelli Fabio Villa Gabriele Sabatini	Porsche 911 GT2	P	83
				Porsche 3.6L Turbo Flat-6
10	77	Seikel Motorsport	Ernst Palmberger Nigel Smith Richard Nearn	Porsche 911 GT2	D	82
				Porsche 3.6L Turbo Flat-6
11	4	Roock Racing	André Ahrlé Hubert Haupt	Porsche 911 GT2	Y	82
				Porsche 3.6L Turbo Flat-6
12	24	RWS Motorsport	Horst Felbermayr, Sr. Horst Felbermayr, Jr.	Porsche 911 GT2	?	81
				Porsche 3.6L Turbo Flat-6
13	10	Marcos Racing International	Cor Euser Mike Hezemans	Marcos Mantara LM600	D	80
				Chevrolet 5.9L V8
14	9	Haberthur Racing	Stefano Bucci Andrea Garbagnati Mauro Casadei	Porsche 911 GT2	D	80
				Porsche 3.6L Turbo Flat-6
15	6	Konrad Motorsport	Franz Konrad Bob Wollek	Porsche 911 GT2	D	79
				Porsche 3.6L Turbo Flat-6
16	26	Grassi	Ruggero Grassi Anssi Münz	Porsche 911 GT2	?	79
				Porsche 3.6L Turbo Flat-6
17	78	Seikel Motorsport	Renato Mastropietro Raffaele Sangiuolo Claudio Padovani	Porsche 911 GT2	D	78
				Porsche 3.6L Turbo Flat-6
18	27	MAC Racing	Luciano Tamburini Ruggero Melgrati	Porsche 911	?	77
				Porsche 3.4L Flat-6
19	16	Freisinger Motorsport	Manfred Jurasz Ray Lintott	Porsche 911 GT2	D	76
				Porsche 3.6L Turbo Flat-6
20	20	Bovi Motorsport	Attila Barta Ferenc Rátkai Kálmán Bódis	Porsche 911 GT2	?	70
				Porsche 3.6L Turbo Flat-6
21	5	Roock Sportsystem	Michael Eschmann Hugh Price John Robinson	Porsche 911 GT2	Y	62
				Porsche 3.6L Turbo Flat-6
22 DNF	22	Paul Belmondo Racing	Emmanuel Clérico Christophe Pillon	Chrysler Viper GTS-R	D	52
				Chrysler 8.0L V10
23 DNF	25	Lister Cars	Julian Bailey Tiff Needell Bobby Verdon-Roe	Lister Storm	M	33
				Jaguar 7.0L V12
24 DNF	28	Ebimotors	Fabio Babini Massimo Frigerio	Porsche 911 GT2	?	27
				Porsche 3.6L Turbo Flat-6
25 DNF	69	Proton Competition	Gerold Ried Christian Ried Patrick Vuillaume	Porsche 911 GT2	Y	25
				Porsche 3.6L Turbo Flat-6
26 DNF	18	Chamberlain Motorsport	Ni Amorim Will Hoy	Chrysler Viper GTS-R	M	6
				Chrysler 8.0L V10

• Pole position – #1 Chrysler Viper Team Oreca – 1:45.344
• Fastest lap – #1 Chrysler Viper Team Oreca – 1:46.278
• Average speed – 185.704 km/h