Imports fell 7% from a year earlier, according to Finance Ministry data released Thursday.
The drop in exports was the worst since October 2009 — amid the fallout from the global financial crisis — as export-dependent Japan struggles to juggle the health risks of COVID-19 with the dire need to keep the economy going.
Exports to regions most badly affected by the pandemic took the biggest hits.
Shipments to the U.S. plunged 38%, while imports rose 1.6%, causing the politically contentious trade surplus to decline by 75% from a year earlier, to 181 billion yen ($1.7 billion).
Japan's exports to the European Union tumbled 28% in April, while imports from the region declined 7%.
Trade with China, which was the early epicenter of the virus outbreak and is now reviving its economy, was less affected. Exports slipped 4% and imports from China jumped 12% year-on-year.
Overall, exports totaled 5.2 trillion yen ($48 billion), down from nearly 6.7 trillion yen in the same month in 2019. Imports dropped to 6.1 trillion yen ($57 billion) from 6.6 trillion yen.
By sector, exports of vehicles, machinery, chemicals and textiles fell most sharply.
Automakers, like Toyota Motor Corp. and Honda Motor Co., which form a pillar of the economy, have reported nose-diving profits as sales shrink around the world and plants in some parts of the world stop production.
“The drop in auto exports, reflecting the lockdowns in Europe and the U.S., is really working to drag down the numbers,” said SMBC Nikko Securities chief economist Junichi Makino, noting electronics exports had held up better.
Japan's exports may start recovering after hitting bottom in the April-June quarter, though much depends on whether the pandemic can be curbed, he said.
Japan is in a technical recession after a contraction that began in the last quarter of last year deepened in January-March. Analysts say worse may lie ahead.
Like many other nations, Japan has asked people to work from home and do social distancing to curb the virus’ spread. Restrictions were eased this month in regions with few or no new infections, though they remain in place for Tokyo and some areas.
Tourism and travel have dwindled. Restaurants are closed or allowing only takeouts, and those that have stayed open are seeing fewer customers.
Even before, the world's third-largest economy barely eked out growth over some periods. The recent trade conflict between China and the U.S. has also hurt Japan.
This story has been corrected to show that Japan's imports from the EU in April declined 7%, not 8%
Yuri Kageyama is on Twitter https://twitter.com/yurikageyama