The median forecast in the survey of 12 economists showed non-oil domestic exports in June were expected to have fallen 2.3 percent from a year earlier, following a 6.6 percent drop in May.
A recent survey by the Singapore Institute of Purchasing & Materials Management showed that the city-state's manufacturing activity grew in June but at the slowest pace in five months due to weak new orders.
In addition, the government's advance estimate of second-quarter gross domestic product released on Monday showed that Singapore's economy contracted in April-June for the first time in nearly two years, hit by a sharp drop in manufacturing activity.
On a month-on-month and seasonally adjusted basis, non-oil domestic exports are seen rising 4.0 percent in June, getting some respite after tumbling 7.5 percent in May.
Singapore's non-oil domestic exports are seen likely to increase this year after having fallen 6.0 percent in 2013, buoyed by an expected improvement in US and European economic growth.
Exports, however, have struggled to gain traction in recent months, partly due to weakness in electronics shipments.
Electronics is a key driver of Singapore's exports but its manufacturers are not as well positioned in the electronics supply chain to gain from growth in demand for smartphones and tablets, compared to peers in South Korea and Taiwan.