Terms of the deal were not immediately available. The former Minnesota Viking had been talking to the Saints since free agency began at the end of February and had been the team most interested in signing him.
"Darren is an accomplished veteran player that brings a wealth of knowledge and ability to our secondary and has always possessed outstanding instincts and playmaking skills," Saints general manager Mickey Loomis said, according to The Associated Press.
The fit is a natural. Sharper's known for his play-making ability and his leadership on the field. By comparison, last year's Saints defense struggled in the secondary and lacked some play-making ability.
The 33-year-old Sharper will be joining his third NFL team in 13 years. The former first-round draft pick of the Packers spent eight seasons with Green Bay before signing with the Vikings in 2005. Sharper has 54 career interceptions and has been to four Pro Bowls.
The Saints also announced that they have signed veteran free-agent tight end Darnell Dinkins to a one-year contract.
Senior writer John Clayton covers the NFL for ESPN.com.