Hereford go into the half time break 1-0 up at Guiseley thanks to a Lenell John-Lewis penalty.
The Bulls striker stroke home the spotkick in the 31st minute after Tom Owen-Evans was deemed to have been upended in the box.
Up until that point, the home side had the better chances with Lebrun Mbeka going close with a header and Jonathan Wafula shooting over.
John-Lewis had Hereford's best chance of the half when he headed straight at Guiseley keeper Brad Wade in the 27th minute before he did open the scoring from the penalty spot just four minutes later.