Diskerud, a U.S. international, has agreed to join the Swedish club until Aug. 27, 2017.
NYCFC bought out Diskerud's guaranteed contract last week, with each MLS club allowed to buyout one player's contract during the offseason to free up salary-cap space.
The 26-year-old remains under contract with Major League Soccer.
Sweden’s Allsvenskan league begins on April 1, and Diskerud will be with coach Jorgen Lennartsson's team throughout most of the MLS season.
Diskerud signed with NYCFC ahead of its inaugural season in 2015. The Norwegian-American had four goals and three assists in 39 appearances in two years with the club