Sales of new cars (excluding mini vehicles), trucks and buses in Japan rose 33.5% in April to 222,095 units.
It was the the ninth consecutive month of increase as auto demand continued to be supported by government tax breaks and subsidies, JADA said.
However, the gain is against depleted sales last year.
Sales of passenger cars in April climbed 36.8% to 200,343 units, according to the association.
Toyota saw its April sales climb 50% to 113,644 units.
Nissan sales increased 31% to 27,728.
The Japan Mini Vehicles Association said sales of mini-vehicles in April rose 10.8 percent to 130,370 units, marking the fourth straight month of growth.