The three time Japan international has penned a four year deal with the club meaning that he is tied to the German club until 2018 at this point in time.
Haraguchi has made 162 appearances in the Japanese top flight despite being just 23 years of age with 33 goals and also 22 assists added to his name.
"Haraguchi can be used in several positions across our frontline. He can play on the left and the right, in the middle or as a second striker," said sporting director Michael Pretz. " We have a lot of different options now in attack."
Along with Haraguchi, Valentin Stocker from FC Basel, Jens Hegeler fro Bayer Leverkusen and also Marvin Plattenhardt from Nurnberg have all joined the club in preparation for next season's Bundesliga.