Yong-tae first started playing football when he was nine years old, and it soon became clear he was naturally gifted. He turned down the chance to join his hometown club, Incheon United, choosing instead to sign for Suwon Bluewings in 2005, aged 19.
He spent two years playing for Suwon's youth team before making the step-up to senior level in 2007, at the age of 21. Yong-tae made 20 league appearances for Suwon across three seasons (2007, 2008 and 2009), scoring twice. In January 2010 he moved to Gwangju Sangmu for an undisclosed fee.
Yong-tae's start to life as a Sangmu player has been mightily impressive, and as of 3 January 2011 he has 16 goals from 19 league matches. Such form has attracted the attentions of several European clubs, with English sides Wigan Athletic and Leicester City as well as German teams 1. FSV Mainz 05 and Energie Cottbus all reportedly interested in signing him in the not too distant future. Yong-tae has also attracted interest from Danish side OB.