The visitors led 19-14 at half-time and went further ahead when centre Stokkies Hanekom crossed for his second try in the 66th minute, pivot Elton Jantjies adding the conversion to make it 26-14.
But shortly afterwards, Dylan des Fountain was sent to the sin bin and the Kings came storming back with lock Steven Sykes powering over.
Replacement George Whitehead missed the extras, but, in the end it proved inconsequential because the Lions did an excellent job of holding the home side at bay late on.
The Kings took a bonus point from the game for ending within seven points of the Lions, but it will be little consolation as they now look ahead to a tough away fixture next weekend.
The Lions were solid through most of the match and their good defence frustrated a number of attacking opportunities enjoyed by the Kings.
Besides Hanekom’s two tries, fly-half Jantjies had a good night with the boot, slotting four penalties and two conversions for a personal contribution of 16 points.
The first half was an evenly fought affair, with the sides trading several penalties before the Kings eventually cracked the visitors’ defence with a well executed cross-kick by flyhalf Demetri Catrakilis after a five-metre line-out.
With Marcello Sampson standing wide on the left, the Kings flyhalf’s accurate kick landed in his hands and he dived over for the first try of the match to put his team back in the lead.
But just as the Kings were building up steam, Hanekom brought them crashing down, when he intercepted inside his own half to race through to score under the posts.
Earlier, the teams traded penalties, with Jantjies slotting four for the Lions and Catrakilis knocking over three for the Kings.
The two outfits will meet again next Saturday at Ellis Park as the Lions look to ensure a possible return to Super Rugby competition at the first time of asking.