Car sales for the first three months of the year are down 14% compared to the same period in 2012, according to figures from the Society of the Irish Motor Industry.
39,511 new cars were sold between January and March of this year, 6,329 lower than in the first quarter of 2012.
Sales in March were 10% lower than in the same month of last year.
With car registrations now split into two six-month periods during the year, the motor trade industry will be hoping that some of the decline will be offset by increased activity in July.
According to SIMI the most popular car between January and March was the Volkswagen Golf, with the German car maker also the most popular brand overall.
94% of the cars sold in the year so far fit into the two lowest CO2 emissions categories, while 72% of the vehicles sold were diesel.