The 19-year-old held an overnight lead thanks to her short programme and scored 132.27 in the free skate to hold onto that advantage, despite a fall.

World champion Kaori Sakamoto had the best free-skate score, 133.80, but it was not good enough to catch Kim.

Kim is the first South Korean to win a Grand Prix of Figure Skating leg since Kim Yuna won three, including the final, in 2009.

Rion Sumiyoshi was third, meaning there were two Japanese skaters on the women's podium.

In the men's competition, world champion Shoma Uno came from behind to claim the win by more than 20 points.

Uno had trailed fellow Japanese athlete Sōta Yamamoto after a sub-standard short programme, but dazzled in the free skate.

Uno scored 188.10 and racked up a total of 279.76 - within a point of the series-leading total American Ilia Malinin posted at Skate America.

South Korea's Four Continents champion Cha Jun-hwan was third.

There was also Japanese success in the pairs, with world silver medallists Riku Miura and Ryuichi Kihara leading from start to finish.

Their free skate was worth 137.91 points, 15 more than their closest rivals'.

Americans Emily Chan and Spencer Akira Howe were second, with Canada's Brooke McIntosh and Benjamin Mimar third.

In the ice dance, however, Canada edged the United States, with Laurence Fournier Beaudry and Nikolaj Sørensen winning their first Grand Prix event.

Impressive lifts helped them to narrowly beat Madison Chock and Evan Bates, bronze medallists at this year's World Championships.

The Canadians were less than a point in front both in the free skate and rhythm dance. 

Caroline Green and Michael Parsons, also American, were third.