Exports in April fell 2.6 percent to 77.42 billion rand, while imports decreased by 1 percent to 90.45 billion rand.
The latest data brings the cumulative deficit for 2014 to 40.96 billion rand compared to 30.66 billion rand over the same period in 2013.
Economists polled by Reuters had forecast a trade shortfall of 12 billion rand for April.