Prices for ad spots last year averaged $1.7m (£1.2m) but this year have come down to anywhere from $1.4m to $1.7m.
As well as slashing prices ABC also decided that it should widen its search for advertisers and is allowing movie studios to buy ads for the first time.
The price drop has been blamed on the recession as car manufacturers and retailers cut back on ad spending but also on declining ratings for the awards show, which some say fails to resonate with younger viewers.
Several long-time Academy Awards sponsors including General Motors and L'Oreal, two of the biggest advertisers in the past, have decided not to run ads this year. GM alone had spent $105m (£74m) over the past decade on Oscar ads, according to TNS Media Intelligence.
Dove soap has also dropped out and American Express, traditionally one of the biggest advertisers in the Oscars, has bought only one spot.
Those companies which are advertising include Hyundai Motors, which bought time in this year's Super Bowl, for which NBC charged an average of $3m (£2.1m) for a 30-second ad. Other companies that have bought spots include JC Penney, PepsiCo's Frito-Lay and Coca-Cola.
The Oscars broadcast is one of the biggest TV events in the US but last year's three-hour show hit a record low averaging 32m viewers, about 1m less than the previous record low in 2003.
The awards face mounting competition from other ceremonies such as the Golden Globes, Emmys and Baftas and there is pressure to jazz up the broadcast to appeal to younger viewers. This reflects an anxiety about the Oscar viewing demographic, which has a median age of 49.5.