The Lionesses dominated for the most part and Belgium had goalkeeper Nicky Evrard to thank for the match staying so tight.
The win was an important one for England, who move up to second in Group A1 and level on points with leaders the Netherlands.
Sarina Wiegman’s side will be back in action on Tuesday, when they travel to face Belgium again in Leuven.
England will want to start that match like they did this one as they nearly blew the visitors away in the opening 15 minutes.
Niamh Charles almost opened the scoring inside a minute thanks to a marauding run that caught the Belgium defence off guard.
The Chelsea left-back was one of England's best performers in the first half, giving the team an attacking outlet down the left after Wiegman ditched a back three to play a 4-3-3 formation.
The Lionesses carried more attacking threat in that shape and took the lead after 13 minutes through Hemp.
Chloe Kelly swung in a corner from the left and, when Millie Bright’s header hit the post, Hemp was there to volley in the rebound.
It was no more than England deserved, but they struggled to get the second goal against a stubborn Belgium side.
Their best chance came around the hour mark when Charles and Hemp combined brilliantly out left, however Alessia Russo couldn’t turn home the cross.
England had 75 per cent possession at the break but just one goal to show for it and Belgium carried a threat on the counter, twice going close from set-pieces.
Their goalkeeper Evrard was also having a great game and meant they remained in the contest.
The chances continued to come for England, but they could not convert. Bright had a header deflected over and Lucy Bronze nodded wide. Russo missed a great opportunity from 10 yards out when Kelly’s shot was blocked.
With just under 30 minutes to go, Fran Kirby was introduced for her first England appearance in a year as the Lionesses chased an elusive second goal.
Alex Greenwood went close to finding it with a free-kick that drew another fine save from Evrard, while Hemp also called the goalkeeper into action after a mazy run that led to her firing a shot on goal.