The Australian Cup and Blue Diamond Stakes will each get a $500,000 prize money boost to $1.5 million.
Racing Victoria also announced on Tuesday the Newmarket Handicap would rise by $250,000 to $1.25 million and the Lightning Stakes and Australian Guineas from $500,000 to 750,000.
As well as increases in nine Group One races, the Blue Diamond lead-ups for colts and geldings will be brought into line with the fillies events.
MELBOURNE AUTUMN PRIZE MONEY INCREASES:
* Australian Cup (2000m, Flemington) - increase of $500,000 to $1.5 million
* Blue Diamond Stakes (1200m, Caulfield) $500,000 to $1.5 million
* Newmarket Handicap (1200m, Flemington) $250,000 to $1.25 million
* Black Caviar Lightning (1000m, Flemington) $250,000 to $750,000
* Australian Guineas (1600m, Flemington) $250,000 to $750,000
* C F Orr Stakes (1400m, Caulfield) $100,000 to $500,000
* Oakleigh Plate (1100m, Caulfield) $100,000 to $500,000
* Futurity Stakes (1400m, Caulfield) $100,000 to $500,000
* William Reid Stakes (1200m, Moonee Valley) $100,000 to $500,000
* Blue Diamond C&G Preview (1000m, Caulfield) $30,000 to $150,000
* Blue Diamond C&G Prelude (1100m, Caulfield) $50,000 to $200,000