Jeremy Fowler of ESPN also confirmed the news.
The 2014 first-round pick recently completed his third year in the league, which means he will remain under contract with the Steelers through at least the 2018 season.
Shazier has lived up to expectations on the field so far, totaling 87 tackles in each of the last two seasons. He was especially useful against the pass in 2016, grabbing three interceptions to go with 3.5 sacks and nine passes defended.
His versatility when attacking the quarterback or dropping into coverage earned him a trip to the Pro Bowl, as well as helping Pittsburgh finish in the top 10 in points allowed.
Unfortunately, health remains a concern for the linebacker. Shazier has yet to play a full 16-game season and has missed 14 total regular-season games in his first three years.
The Steelers will hope their talented young defender can stay on the field for the next two years while he remains under team control.