Lawrence attended Butler Community College from 2010 to 2011. He transferred to Boise State University before the 2012 season. In his first year with the Broncos, he led the team in sacks with 9.5. In 2013, he again led the team with 10.5 sacks. After the season, he entered the 2014 NFL Draft.
After releasing franchise career sack leader DeMarcus Ware in a salary cap move and having previously lost starters Jason Hatcher and Jay Ratliff, the Dallas Cowboys looked to improve the talent of their defensive line in the 2014 NFL Draft. The team traded up with the Washington Redskins moving to the 34th position, in exchange for a second and a third round draft choices, in order to select Lawrence in the second round. After fracturing his right foot in training camp, he started the year on the injured reserve list and did not appear in a game until Week 9 against the Arizona Cardinals. The lost time affected his play and with little impact, he could not earn the starter right defensive end job ahead of Jeremy Mincey. He played a significant role in the against the Detroit Lions on January 4, 2015, with the Cowboys leading 24–20 and just over two minutes remaining in the game, quarterback Matthew Stafford fumbled deep in Detroit's territory. Rather than falling on the ball to down it and securing the game-clinching turnover, Lawrence attempted to pick it up and score, which resulted in his fumbling the ball back to the Lions. He redeemed himself on the ensuing drive, on 4th and 3 with a minute left and the Lions threatening to win the game from the Cowboys' 42-yard line, he sacked Stafford, causing a fumble and recovering it all in one play, sealing the victory. He had a strong showing in the playoffs with two sacks, a forced fumble and two fumble recoveries.
2015
In 2015, although defensive endGreg Hardy was the big offseason acquisition by the Cowboys, Lawrence had a bigger impact from his left defensive end position. He entered the season with an improved physical presence and would develop his edge rushing skills with every passing week. He finished the season with a streak of seven games with at least a sack, registering a total of eight, 31 quarterback pressures and 56 tackles. His best games came against the New Orleans Saints, Tampa Bay Buccaneers, Washington Redskins, and the New York Jets. In January 2016, he had back surgery, which turned out to be more serious than originally expected.
2016
On June 30, 2016, Lawrence was suspended for four games, after his appeal was denied. Lawrence was relatively unproductive during the 2016 NFL season, only registering one sack in 12 games played, this year at right end.
2017
Lawrence had a breakout season in 2017 after shifting back over to the left side, his natural position. On September 17, 2017, in Week 2 against the Denver Broncos, Lawrence forced a fumble off quarterback Trevor Siemian. The fumble helped set up the Cowboys on a touchdown-scoring drive in the 42–17 loss. In Week 3 of the 2017 season, Lawrence sacked Arizona Cardinals' quarterback Carson Palmer three times, giving him the league-lead 6.5 sacks. His performance in Week 3 earned him NFC Defensive Player of the Week. Lawrence's 6.5 sacks was enough to earn NFC Defensive Player of the Month honors, for the month of September. On December 19, 2017, after a breakout season with 14.5 sacks, Lawrence was named to his first Pro Bowl. His 14.5 sacks finished tied for second in the league with the Jaguars'Calais Campbell behind the Cardinals' Chandler Jones. He was ranked 34th on the NFL Top 100 Players of 2018.
2018
On March 5, 2018, the Cowboys placed the franchise tag on Lawrence, who officially signed it later that day after they were unable to come to terms on a long-term deal. In Week 4 of the 2018 season, against the Detroit Lions, Lawrence matched his career-high with a three-sack performance. On October 13, 2018, it was revealed that Lawrence was diagnosed with a torn labrum in his shoulder, in which the injury was intact for two years. He finished the 2018 season with 10.5 sacks, 64 total tackles, 23 quarterback hits, one interception, and two forced fumbles.
2019
On March 4, 2019, the Cowboys placed the franchise tag on Lawrence, making him the highest paid defensive end in the NFL. On April 5, 2019, the Cowboys signed Lawrence to a five-year, $105 million contract with $65 million guaranteed. In week 7 against the Philadelphia Eagles, Lawrence recorded a sack forced fumble on Carson Wentz which was recovered by teammate Antwaun Woods in the 37–10 win. This was Lawrence's first sack in a game against the Eagles.
