He played college football for the Ohio State Buckeyes, and was selected by the Steelers in the first round of the 2011 NFL draft.

[3] Heyward amassed 48 total tackles and 3.5 sacks in his senior season, returning an interception for a career high 80 yards against Miami.

After the combine, he was projected to be selected in the first or second rounds because of the large number of defensive end prospects that were graded highly.

[12] He entered training camp competing with veterans Brett Keisel, Aaron Smith, and Ziggy Hood for a starting defensive end position.

On October 9, 2011, Heyward recorded his first career sack on Tennessee Titans quarterback Matt Hasselbeck, while also making two solo tackles in a 38–17 victory.

[14] He finished the season with 11 combined tackles, a sack, a forced fumble, a pass deflection, and he blocked a field goal in 16 games.

On January 8, 2012, Heyward appeared in his first career postseason games and made four combined tackles in a 29–23 overtime loss to the Denver Broncos.

The next week, Heyward recorded a solo tackle and made his first sack of the season on Mark Sanchez as the Steelers routed the New York Jets 27–10.

On December 30, 2012, he collected a season-high four combined tackles and was credited with half a sack in Thad Lewis during a 24–10 win over the Cleveland Browns.

On September 22, 2013, he earned his first career start in place of weakside defensive end Ziggy Hood and finished the 40–23 loss to the Chicago Bears with one solo tackle.

On November 3, 2013, he made five combined tackles and earned his first sack of the season on Tom Brady, as the New England Patriots routed the Steelers 55–31.

[16] In Week 14, he made a season-high ten combined tackles, a sack, and a pass deflection during a 34–28 loss to the Miami Dolphins.

[17] Throughout training camp he competed with Brett Keisel, Stephon Tuitt, and Cam Thomas to be a starting defensive end.

On October 3, 2014, Heyward was fined $22,050 by the NFL for using abusive language towards an official during Week 4 loss to the Tampa Bay Buccaneers.

On December 21, 2014, Heyward recorded four combined tackles and was credited 1.5 sacks on Alex Smith during a 20–12 victory over the Kansas City Chiefs.

[24] Heyward started at defensive end in the Pittsburgh Steelers' season-opener against the Washington Redskins and collected two combined tackles in a 38–16 victory.

On October 2, 2016, Heyward recorded a season-high seven solo tackles, two pass deflections, and sacked Alex Smith a career-high three times, as the Pittsburgh Steelers routed the Chiefs 43–14.

[25] On November 13, 2016, Heyward suffered a torn pectoral muscle during the Steelers loss to the Dallas Cowboys where he recorded two solo tackles.

[29] On November 27, 2017, Heyward recorded a season-high six combined tackles and had two sacks on quarterback Brett Hundley in the Steelers' 31–28 victory against the Green Bay Packers in Week 12.

[30] Head coach Mike Tomlin elected to rest Heyward during a Week 17 win against the Browns as the Steelers had already clinched a playoff berth and first round bye.

[31] Heyward finished the season with 45 combined tackles (30 solo), a career-high 12 sacks, and three pass deflections in 15 games and 15 starts.

[42] In Week 1 against the New York Giants on Monday Night Football, Heyward recorded his first career interception off a pass thrown by Daniel Jones during the 26–16 win.

[44] Heyward finished the 2020 season recording 54 total tackles (30 solo, 24 assisted) four sacks, five stuffs, one interception and three passes defended.

[48] Across the final three games of the season, Heyward made one sack in each on Patrick Mahomes, Baker Mayfield, and Lamar Jackson respectively.

[49] In the regular season, Heyward recorded ten sacks, 89 total tackles (53 solo), one interception, nine passes defended, and one forced fumble.

[51][52] Heyward and the Steelers achieved another post-season appearance facing off against the Kansas City Chiefs in the AFC Wildcard round.

During the game, Heyward recorded four tackles and a forced fumble that T.J. Watt returned for a touchdown as the Steelers ended their season losing 21-42.

Cameron stated that being part of the NFL was a blessing and he wanted to honor his dad and raise cancer awareness.