The Denmark international left-back had been without a club after leaving AZ, but has joined the Genoese outfit on a three-year deal
The left-back had previously been linked with numerous clubs after featuring at Euro 2012, with Ajax, Aston Villa and Deportivo La Coruna all rumoured to be courting the 27-year-old.
The Dane had previously spent four years in Netherlands, after joining from Midtjylland before agreeing a move to Ciro Ferrara's side.
The player will sign a three-year contract after undergoing a medical examination on Monday, and will wear the No.15 shirt, and could make his debut against Siena next week, the club have confirmed.
Sampdoria open their Serie A campaign against AC Milan on Sunday.