Exports dropped 11.7 percent in March year-on-year, data from trade agency Enterprise Singapore showed, slowing from the revised 4.8 percent growth the month before.
The drop came in much wider than the 2.1 percent decline predicted by economists in a Reuters poll.
This comes amid a tariff dispute between the United States and China - two of Singapore's biggest export markets - which has disrupted global supply chains in a blow to growth in many trade-reliant economies including the city-state.
March's print was the biggest on-year decline since October 2016, when exports dropped 14 percent year-on-year, Refinitiv data showed.
"We now see that the decline is broad-based," Maybank Kim Eng economist Lee Ju Ye told Reuters.
"It is not just electronics, but pharmaceuticals as well."
Pharmaceutical exports, a sector known to be volatile, dived 36.5 percent in March from the previous year after posting a 12 percent growth in February.
Electronics exports in March plunged 26.7 percent year-on-year after an 8.2 contraction in February.
On a seasonally adjusted month-on-month basis, exports contracted 14.3 percent in March after growing 16 percent in February. The poll called for a 7.1 percent contraction from the month before.
Last week, Singapore reported its weakest on-year economic growth in almost a decade.
"There may be a potential revision given that the trade numbers were quite weak," Lee said.
Singapore's central bank last week also kept its monetary settings unchanged after two consecutive rounds of tightening, citing slower growth and inflation as well as "significant" global economic risks.
(Reporting by Fathin Ungku, Editing by Sherry Jacob-Phillips)
By Fathin Ungku