Official figures show that new car sales jumped by 56% last year compared with the 2009 figure.
The Central Statistics Office said 84,907 new cars were licensed last year, up from 54,432 in 2009.
The figures are in line with earlier figures from the motor industry.
Sales last year were boosted by the scrappage scheme introduced in the Budget in December 2009, but they are still well below 2008's figure of 146,470.
Just under 32% of last year's new cars were petrol-powered, while 63.6% were diesel.
Ford led the way with 10,650 new cars, followed by Toyota (10,434), Volkswagen (9,987) and Renault (9,632).
The total number of all vehicles licensed last year was 103,076, an increase of 41%.
The CSO said 647 new cars were licensed in December, an increase of 36.5% from December 2009.