Olympic champion Kim leads in season debut
Kim Yu-Na of South Korea skates in the 2013 World Figure Skating Championships Gala in London, Ontario, on March 17, 2013
The 23-year-old has been off the ice since picking up a metatarsal injury in her right foot in September, but is working herself back to competitive shape in an attempt to defend her Olympic title in Sochi in February.
Dressed in bright yellow, Kim skated to 'Send in the Clowns,' opening with a triple-triple toeloop combination jump, and also included a triple flip but fluffed her double Axel as she put her hand on the ice.
Despite the errors she scored 73.37 points to take an early lead with the free skating final set for Saturday.
It was the best score in the short programme this season, bettering the 73.18 achieved last October by her Japanese rival Mao Asada, who is currently leading the Grand Prix final underway in Fukuoka.
Japan's two-time former world champion Miki Ando, returning to competition after having a baby girl in April, skated to Frank Sinatra's 'My Way' and was sitting second with 62.81.
Russia's Elizaveta Tuktamysheva is third 58.81.
The event will be Ando's last before the 2007 and 2011 world champion attempts to make the Olympics at Japanese nationals later this month.
Kim is bidding to become just the third woman to win back-to-back Olympic figure skating titles and first since since Germany's Katarina Witt in 1984 and 1988.
Known as "Queen Yu-Na" in her native country, Kim won silver at the 2010 worlds, after which she took a lengthy break.
In March she won her second world title in Canada, setting herself up as a strong contender for Olympic gold.
Kim has said that she would retire after the 2014 Winter Olympics and seek to become a member of the International Olympic Committee.