The Kings announced the deal Wednesday.
Andreoff was a restricted free agent after getting two goals and one assist in 18 games last season for the Kings. He made his NHL debut last Oct. 14 and appeared intermittently in Los Angeles' lineup, scoring two points in the Kings' regular-season finale.
Andreoff plays on the wing and at center, where he won more than half of his faceoffs. He will compete for a job in the Kings' lineup in training camp.