Gross written premium fell by an annual 14% through September to 245.3 million lei, Ardaf said in a statement.
Income from mandatory car insurance accounted for around 57% of the company's total premiums in the first nine months of 2009.
Claims paid by the insurer over the same period rose by 55% year-on-year to 186.7 million lei.
In July, Generali PPF Holding, an insurance joint venture of Czech PPF Group and Italy's Generali, raised its stake in Ardaf to 98.87% from 82% following a buyout bid.
Ardaf, set up in 1992, is based in the northwestern city of Cluj.
Ardaf shares were trading down 0.99% at 0.1 lei by 1115 GMT on the over-the-counter market RASDAQ on Wednesday.
(1 euro = 4.295 Romanian lei)