The Korean club expressed an interest in the 28-year-old, whose contract with the Reds was set to expire at the end of the 2011-12 season.
"I've always had an ambition to play overseas and this is a great opportunity to do that," Fyfe said. "It was a really tough decision to make leaving Adelaide at this time with the club in a good position to try and win the championship, but opportunities like this don't come around every day.
"It's a step forward in my career and I've got no doubt my team-mates here can win the A-League title without me."
Adelaide's Dutch coach Rini Coolen confirmed the Reds have secured a back-up for the defender, to be announced next week.