It was the second success in as many weeks for the men in black on the eight-round 2009-2010 circuit after the traditional masters of the abbreviated version of rugby union failed to win a tournament last year.
Winning in Dubai and the Western Cape town of George gives New Zealand 48 points going into the Christmas break and a 12-point advantage over Fiji with Samoa third a further eight points back after two rounds.
A Ben Souness try converted by Tomasi Cama gave New Zealand a 7-0 half-time lead at Outeniqua Park and when a try by veteran forward-cum-skipper DC Forbes soon after the break was converted the advantage doubled.
An Osea Kolinisau try converted by William Ryder cut the deficit in half only for a Save Tokula try to put the eight-time world champions back in control of the final.
Ryder completed the scoring with a late try he failed to convert, leaving the Kiwis with an unassailable nine-point advantage as time ticked away on a warm evening in the south-west tourist town.
Long-serving New Zealand coach Gordon Tietjens praised his 12-man squad which is a mix of youth and experience after a third success in four George finals against the talented but error-prone Fijians.
He said: "The final was different from our two previous matches in that we took the lead and stayed ahead.
"Captain DJ Forbes led by example and younger members of the squad can only learn from him.
"We have made the perfect start with two victories after a terrible time last year.
"There is a long way to go but we will take it one tournament at a time and give it our best shot," he promised.
New Zealand overcame a 14-point deficit to pip England 22-19 in the quarter-finals after finishing only second in their group following a first-match loss to Samoa in a repeat of the Dubai decider.
The Kiwis conceded a 13-second try to Kenya in the semi-finals and trailed by nine points at half-time before another recovery delivered a 17-14 triumph with Zar Lawrence snatching the crucial third try.
Defending World Series champions South Africa failed to get beyond the last eight for the second consecutive weekend, losing 21-17 to Fiji, and the host nation also flopped in the Plate final against England.
December 2009: New Zealand coach in confident mood after Dubai victory
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