The Titans announced the deal Sunday night.
The 6-foot-3, 214-pound Decker visited the Titans on Wednesday, met with coach Mike Mularkey and took a physical. He was released this month by the Jets after three seasons with the team.
Decker, who spent his first four seasons with Denver, has three 1,000-yard seasons with 12 100-yard games in his seven-year NFL career. He has 33 touchdowns in the red zone since 2012, second in the NFL only to Brandon Marshall (35) in that span. He also ranks 18th in the NFL with 43 touchdown receptions and 4,535 yards receiving since 2012.
Hip and shoulder injuries limited Decker to three games last year.
Decker said on Twitter that he’s “excited” to join the Titans, who finished 9-7 last season but missed the playoffs.
Meanwhile, Decker’s former teammate Brandon Marshall, now with the Giants, said he thought the Titans landed a good player.
(© Copyright 2017 CBS Broadcasting Inc. All Rights Reserved. The Associated Press contributed to this report.)