Ulster were in hot form from the outset and dominated the first half completely, which saw them outscore the hosts five tries to one for a rewarding 35-10 halftime lead.
The second half proved to be much more competitive as the Isuzu Southern Kings stepped up their attack and tightened up their defence, which saw each team score only once more, although the men from Port Elizabeth were again left ruing missed opportunities after battling to capitalise on a few chances.
The visitors scored their first try in the second minute compliments of John Cooney (scrumhalf), who picked up the ball from a ruck following several phases on attack and navigated his way through the defence.
Isuzu Southern Kings flyhalf Demetri Catrakilis responded with a penalty goal, but this proved to be their only points until the dying minutes of the half as Ulster scored four more tries to inflate their lead to 35-3.
Luke Marshall (centre) scored their second try in the 16th minute after receiving the ball out wide and stepping on the gas without any defenders in sight, and Rob Herring (hooker) followed thanks to some good running and support play.
The home side tried hard to force their way back into the match by retaining possession, but they battled to breach the effective defence, and found themselves making unforced errors at vital times.
Ulster, in turn, continued their fine attacking form with Matt Faddes (fullback) scoring their bonus-point try in the 31st minute from a perfectly-timed chip through into space, and Cooney secured his brace soon after as he receiving a well-timed pass from Marcell Coetzee (No 8), who made a great break in the middle of the field.
Despite this, the Isuzu Southern Kings never gave up, and their determined efforts paid off as Tertius Kruger (centre) touched down shortly before the break after beating a defender near the poles, and the successful conversion saw them enter the break trailing 35-10.
The hosts had two opportunities to add to their score in the third quarter, but they were unable to capitalise on this.
In stark contrast, Ulster added their sixth try on the stroke of the fourth quarter with Sean Reidy (flanker) crossing the chalk from a rolling maul, but they were dealt a blow minutes later, losing Adam McBurney (replacement hooker) to a yellow card.
The Isuzu Southern Kings took full advantage of this with Aston Fortuin (lock) crossing the tryline in the 69th minute from some strong forward play, and the successful conversion saw them trail 42-17.
They continued to show their fighting spirit until the final hooter, and made their way close to the tryline on occasions, but they unable to come away with points.
The Isuzu Southern Kings will have a bye next week before embarking on a four-week tour where they will line up against Benetton, the Glasgow Warriors, Ospreys and Connacht respectively.
Isuzu Southern Kings 17 (10) – Tries: Tertius Kruger, Aston Fortuin. Conversions: Demetri Catrakilis (2). Penalty Goal: Demetri Catrakilis.
Ulster 42 (35) – Tries: John Cooney (2), Luke Marshall, Rob Herring, Matt Faddes, Sean Reidy. Conversions: John Cooney (6).