The victims were four women, two men and one girl, said Fahad Al Ghamdi, a spokesman for the Red Crescent in the Eastern Province, Saudi media reported on Thursday.
The tragedy happened at around 10:30am and reports said a third car was involved in the accident.
In a separate accident in the gulf country, two young men were killed when their car crashed into a lamppost in Al Ihsa, an oasis region in eastern Saudi Arabia.
Road accidents are numerous and often tragic on Saudi roads despite regular campaigns launched by the authorities to promote a safer traffic culture.
The massive presence of trucks and trailers and a tendency by all drivers to speed are often blamed for the alarmingly high figures of accidents.