Amendola had expressed his desire to stay with the Patriots earlier this offseason.
Amendola should be able to play a prominent role in Miami.
The Dolphins need help at receiver after trading Landry to the Cleveland Browns for a 2018 fourth-round pick and a 2019 seventh-round pick after not being able to agree to terms on a long-term deal with the three-time Pro Bowler.
The 32-year-old is coming off his best season as a Patriot finishing with 61 catches for 659 yards and two touchdowns, but made his biggest impact in the postseason by hauling in 26 passes for 348 yards and two touchdowns.
Amendola will be joining a slightly revamped Dolphins receiving corps which also includes the recently-signed Albert Wilson as well as holdovers Kenny Stills and DeVante Parker. The deal can not be officially signed until March 14, which is the start of the new league year.
Amendola also served as New England's top punt returner after Julian Edelman and Cyrus Jones both suffered torn ACLs during the preseason.