New Zealand golfer Lydia Ko’s latest win has boosted her world ranking to No.2, trailing only South Korea’s Inbee Park.

Park has spent the last 55 weeks in the No.1 spot, but Ko is looking threatening after moving up two places from fourth following her win at the $US1.8 million ($A1.95 million) Swinging Skirts LPGA Classic in California on Monday.

The 17-year-old beat world No.3 Stacy Lewis of the United States by one stroke to pocket $US270,000 ($A292,000).

It was her second win since turning professional last October, with her first in December when she won the Swinging Skirts World Ladies Masters in Taiwan.

Ko had previously won five pro tournaments as an amateur, including LPGA wins at the 2012 and 2013 Canadian Opens.