Official documents reveal tougher exhaust emission standards could raise the cost of a used vehicle by up to $5000.
From January, vehicles that do not comply with what is known as the Japan 05 standard will not be allowed into the country.
A Ministry of Transport report from July outlines the possible effects that will have on vehicle prices.
They include consumers potentially needing to spend $2000 - $5000 more to buy a newer imported vehicle that meets the standard. Imported Motor Vehicle Industry Association chief executive David Vinsen says cheaper vehicles will not be able to come in and vehicles which do come in will be newer and therefore more expensive.
Greater demand for those newer vehicles will force up the price, he says, and as a consequence the price of vehicles already in the country will go up.
The Ministry says people will not be priced out of the market if they buy privately or at auction, or from a dealer who stocks up with imports prior to January.