In China, she is referred to as the "female Liu Xiang", in respect of her more successful hurdling compatriot.

[5] Sun made improvements in the 2009 season, which began with her winning her first national title with a best of 13.15 seconds.

She ran faster (13.12) in the heats at the 11th Chinese National Games,[6] but was not as quick in the final – the more experienced Liu Jing edged Sun into second place.

[10] She repeated as the national champion and represented her country in the Décanation event in France, coming fourth.

[4] She was among the favorites for the hurdles at the 2010 Asian Games, but it was Korean Lee Yeon-Kyung who went away with the gold, while Sun had to settle for the bronze medal.