Although no financial details were disclosed, local media estimate Ryan's deal with the Ducks is worth $25.5 million.
Ryan, who won a silver medal with the United States at the 2010 Vancouver Olympics, scored a career-high 64 points for the Ducks last season and led the team with 35 goals.
A restricted free agent after his first two full seasons in the NHL, Ryan initially wanted to settle for a shorter second contract with Anaheim before agreeing to a five-year deal.
The Ducks were keen for the young winger to remain with the team beyond the current terms agreed by fellow forwards Ryan Getzlaf and Corey Perry.
"They would like me to hold down the fort in case one of those guys goes elsewhere," Ryan said on a conference call.
"The biggest thing for me was trying to figure out where those guys were going to be moving in three years. After speaking with those guys, they are both committed to this team and organization. I felt a lot better doing a five-year deal."
(Writing by Mark Lamport-Stokes in Los Angeles; Editing by Frank Pingue)