Creamer will lend name recognition to the event, as one of the most famous and long-tenured female golfers.
Creamer has spent 13 years on the LPGA Tour, winning 10 titles and sitting 10th all-time in career earnings with over NZ$16 million.
While in decent form of late, Creamer hasn't won on Tour since 2014, and has dropped to 112th in the world.
Tournament director Michael Goldstein is pleased to have locked in the two high profile players.
"Paula is one of the superstars of women's golf and it is wonderful that she is coming to New Zealand. As well as being a golfer of the highest level, she is such a respected figure in the sport," said Goldstein.
"Danielle is one of the exciting new wave of young players on the LPGA who is on top of her game after winning the PGA Championship a few weeks ago."
With the additions of Kang and Creamer, the Open will now boast a field with 16 major championships won between them. Yani Tseng (5), Lydia Ko (2) and Brittany Lincicome (2) are all multi-major winners, while Brooke Henderson, Catriona Matthew, Na Yeon Choi, Eun-Hee Ji and Hyo Joo Kim have all also raised a major trophy.
The field for the Open will be finalised this week, with the event being held from September 28 to October 1.