Per Lindsey Thiry of ESPN, Woods will receive $32 million guaranteed.
The Rams did not disclose terms but confirmed the news.
Woods had been scheduled to become a free agent after the 2021 campaign, but he is now signed through the 2025 season.
The 28-year-old has been a favorite target of quarterback Jared Goff since signing with the Rams in 2017. He had six catches for 105 yards in the team's 20-17 season-opening win over the Dallas Cowboys on Sunday.
Woods entered the league out of USC as a second-round pick of the Buffalo Bills in 2013, and while he was a solid secondary option in Buffalo, he never recorded more than 699 yards or five touchdowns in a single season.
Since signing with Los Angeles, however, Woods has blossomed and developed into a No. 1 option in one of the NFL's best offenses.
He has posted back-to-back 1,100-yard seasons and caught a career-high 90 passes last year.
That left Woods as the unquestioned top outside wideout since Kupp primarily works out of the slot.
With Woods having proved himself as Goff's go-to guy, the Rams made a sensible move by rewarding him with a new deal and locking him in for the foreseeable future as they try to return to the Super Bowl.
Woods may never be viewed as on the same level as stars Michael Thomas, Julio Jones, DeAndre Hopkins and Davante Adams, but he has quietly become one of the best and most consistent pass-catchers in the NFL.