The 29-year-old custodian, first choice for both current side Viking FK and his country of birth, will be joining Hertha from 1 January 2014 and has put pen to paper under a two-and-a-half year contract that will keep him at the newly-promoted club until 2016.
'I'm very excited'
"We're very glad Rune Jarstein has opted to join us," said sporting director Michael Preetz. "His experience will help our very young group of goalkeepers."
Jarstein said he jumped at the chance of joining the capital city side. "I'm really looking forward to playing for Hertha as well as in Berlin. The Bundesliga's a big challenge, and I'm very excited. Hertha have been having a brilliant first half of the season, and I want to help the club achieve its targets."