Japan's trade deficit hit 952.6bn yen ($9.9bn; £6.8bn) in January, the largest since records began in 1980. Demand for Japanese cars in particular dropped by 69%.
Trade in electronics and other goods has also slumped as global economies and consumer spending contract, pushing Japan deeper into recession.
Japanese exports to the US, which is at the centre of the slide, fell nearly 53% in January while shipments to the European Union retracted by 47%, Japan's finance ministry said.
"Exports to Asia, particularly to China, are tumbling at about the same pace as shipments to the United States, signalling that even China's economy may be shrinking," said Takeshi Minami, chief economist at Norinchukin Research Institute.
Exports to Asia dropped 47%, while those to China fell 45%.
Japan's export-led economy had previously been thought to be immune to the worst effects of the global recession, the AFP news agency reported.
The government said last week that Japan's economy was in its most serious crisis since World War II, after it contracted at an annualised rate of 12.7% in the last quarter of 2008.
This was its worst performance in almost 35 years, officials said.
In response, the government is pushing bills through parliament to implement a stimulus plan, including a cash handout of at least $130 for each Japanese taxpayer, the BBC's Roland Buerk reports from Tokyo.
But any bold moves may be difficult to push through because of the unpopularity of Prime Minister Taro Aso, our correspondent says.
US President Barack Obama and Mr Aso have agreed to work together to stimulate economic demand and fight protectionism as the latter visits the US.
The US and Japanese economies are respectively the world's largest and second-largest.
