The move to Italy will be the 28-year-old's first trip abroad.
In addition to Häcken and Kopparbergs/Göteborg FC, Hammarlund has also represented Tyresö and Piteå in the women's league.
- It was a tough decision because it is difficult to leave something that has been as good as Häcken.
It's really a fantastic club to play for, but I felt ready for an adventure abroad, she says to Häcken's website.