A record number of 468,624 students from 2,760 schools entered the 1990 AMC.

Results are given below for the 1990 AMC, held on Tuesday 31 July. There were 2 perfect scores.

Medals were presented at a function held at Government House, Sydney, on Monday 29 October, by the Governor of New South Wales, His Excellency Rear Admiral Peter Sinclair AO.

The medallists were:

AMC Medallists from the Junior, Intermediate & Senior Divisions
NAME	SCHOOL		YR
BISHOP Andrew	Pulteney Grammar School	SA	8
BRINK Simon	Melbourne C of E Grammar School, Wadhurst	VIC	8
CHAU John	Bayswater High School	VIC	8
JAANISTE Luke	Maroochydore State High School	QLD	8
KIERNAN Gareth*	Kuranui College	NZ	8
LARAGY Sybil	Wesley College	VIC	8
LAU Karen	Tintern C of E Girls Grammar School	VIC	8
MAILES Oliver	Christ Church Grammar School	WA	7
MAYFIELD Anthony	Hurlstone Agricultural High School	NSW	8
PON Karen	Leeming High School	WA	8
WILKINSON Michael	Newington College	NSW	7
BRISTOW Keir	Melbourne C of E Boys Grammar School	VIC	10
BURTON Benjamin	John Paul College	QLD	10
CAI Zheming	The Chinese High School	SIN	10
CHAN Andrew	Eltham College	VIC	10
ELLIOTT David	Trinity Grammar School	NSW	10
HENDERSON Anthony*	Sydney Grammar School	NSW	9
MACDONALD Jonathon	Awatapu College	NZ	10
OPPENHEIM Andrew	Melbourne C of E Boys Grammar School	VIC	10
RICKS Jonathan	The Friends School	TAS	9
SMITH Roderick	Forster High School	NSW	10
ADAM Timothy	Scotch College	VIC	12
BRINSMEAD Thomas	Lambton High School	NSW	12
DYKE Kieran	Modbury School	SA	12
GIFFORD David	Canberra Grammar School	ACT	12
LAU Joseph	North Sydney Boys High School	NSW	12
PHILLIPPS Andrew	Wellington College	NZ	12
WONG Alan	Sydney Technical High Schoo	NSW	12
YIP Dominic	Crows Nest Boys High School	NSW	12

Two Intermadiate medallists, Benjamin Burton and Anthony Henderson, were to go on and win IMO Gold Medals. Both now teach mathematics at Australian Universities, Benjamin at the University of Queensland and Anthony at the University of Sydney.