The 22-year-old came to Germany from Jeju United on January 30, 2011, and leaves Lower Saxony having neither scored nor assisted a goal in 12 appearances during the 2011-12 season.
"We are happy that the signing of Koo Ja-Cheol has worked. We were interested in signing the player some time ago, but it did not work out," FCA director Andreas Rettig said. "Our special thanks to the management at VfL Wolfsburg, led by Felix Magath: without their support, the transfer would not have been possible."
The player himself was delighted to move to Bavaria, and vowed to help his team avoid relegation.
"I am glad that my move to Augsburg worked, and I will give everything so that FCA can celebrate their staying in the Bundesliga at the end of the season," Koo said.
The versatile midfielder joins an Augsburg side that are 17th in the Bundesliga standings, with just 16 points from 19 games - four behind the safety of 15th place.
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