The country's trade surplus for the month was $111m, down from $1.1bn last year.
The result marked a second straight month of surplus, but was worse than the surplus of $835m last month.
Foreign market dependence
Japan's heavy dependence on foreign markets has left its economy one of the worst affected by the global economic downturn and, according to analysts, is firmly on course for its worst recession since the second world war.
Shipments to the US and Europe have more than halved as demand for cars and electronics plummeted, while goods sent to China have dropped.
The world's second-largest economy also recorded its worst performance in nearly 35 years in the last quarter of 2008, contracting at an annualised rate of 12.1 per cent.