The Serbian youngster traveled to Germany earlier this week and has now completed his move to the Bundesliga outfit, signing a four-year deal.
Last year's Champions League finalist was keen to add to its ranks after Jakub Blaszczykowski was ruled out for the remainder of the season due to a knee injury and the club has now found its man in 21-year-old Jojic.
The attacking midfielder has signed a four-and-a-half-year deal with the Bundesliga giant.
"We're very happy with the signing of Milos Jojic. He is a player who is very versatile in midfield and who has a lot of potential. He completes our squad," sporting director Michael Zorc commented on the move.
Jojic came through the ranks of the Partizan youth academy and made his official first team debut in 2012-13 after a previous loan spell with Teleoptik.
He had since developed into a key player with the Belgrade outfit and his continued good form this season earned him a switch to Signal Iduna Park.
Jojic has been capped at senior level for Serbia, scoring on his international debut against Japan in Oct. 2013.