Banyana, who finished in second place in Group C behind Korea DPR, scored the opening goal through the experienced Noko Matlou in the 18th minute, which was the side's second goal in the competition. It was Matlou's 64th goal in her 140th appearance for Banyana.
However, the South Africans were unable to take their lead into the break as striker Tessa Wullaert equalised for the Belgians. It was the first goal Banyana conceded in the competition, having kept three clean sheets in the group stages.
Desiree Ellis' ladies held their own in the second period as they tried to get a winning goal, but it was not to be as the Belgians scored a late winner through Yana Daniels.
With five shots on target throughout the game, compared to Belgian's two, Banyana should have won the game.