Saab saw a 31.5 percent drop in the number of vehicles sold in September compared with the previous year.
Volvo car sales also dipped by 14 percent to around 20,900 vehicles sold in Europe in September.
Through the first nine months of 2008, Volvo car sales have dipped 11 percent, according to statistics from the European Automobile Manufacturers Association (ACEA).
Saab sold around 5,900 cars in Europe in September and has seen sales fall by 17.8 percent since the start of the year.
Other brands which have suffered include Alfa Romeo, Land Rover, and Lexus, all of which are dealing with 25-30 percent drops in sales compared to September 2007.
Overall, European car sales for September are down 8.2 percent, with a total of 1.3 million new registrations recorded. Not since 1998 have so few cars been sold in Europe during September.