Levy was born in Milwaukee, Wisconsin, where he attended Vincent High School and was a letterman in football, basketball, and track. As a senior, he recorded 84 tackles, five sacks, and four forced fumbles as a linebacker and 12 receptions for 260 yards and three touchdowns as a tight end.
Levy played college football at Wisconsin from 2005 to 2008. He finished his career with 211 tackles, 21 sacks, two interceptions, six forced fumbles, six fumble recoveries and a blocked kick.
In November 2006, Levy inadvertently collided with nearly 80-year-old Penn State coach Joe Paterno on the sideline during a game, fracturing Paterno's shin bone and damaging knee ligaments. Years after the discovery of the Penn State child sex abuse scandal, Levy called this accidental hit his "proudest college moment". In response, 21 former Penn State football players signed a letter condemning his comments.
Levy was named second-team All-Big Ten in 2007. In 2008, he earned honorable mention All-Big Ten, and was also awarded the team's Tom Wiesner Award, given to a senior football player who most exemplifies the leadership and courage.In addition to twice winning the Big 10 Player of the Week, in 2008, he was also awarded the Bronko Nagurski National Defensive Player of the Week on September 13 for his performance against Fresno St.
Levy was drafted by the Lions in the third round of the 2009 NFL Draft.
As a rookie, Levy started 10 of 16 games for the Detroit Lions, recording 85 tackles and an interception.
In 2010, Levy was limited to only 11 games, missing Detroit's Week 1, 2, 4, 5, and 6 games.
For the season, Levy recorded 72 tackles, 2 interceptions, and 4 pass-breakups. In Week 14, against the eventual Super Bowl Champion Green Bay Packers, Levy had 8 tackles and an interception of Packers QB Matt Flynn in the endzone in a 7-3 Lions win. In Week 16, against the Miami Dolphins, Levy returned an interception of Chad Henne 30 yards for the game-winning touchdown in a 34-27 win.
In his third season, Levy started all 16 games for the Lions, recording 109 tackles, a sack, an interception, and a forced fumble.
In 2012, Levy started 13 games for the Lions, recording 82 tackles, and 1 interception.
In 2013, Levy started all 16 games for the Lions, recording 119 tackles, and 6 interceptions.
In 2014, Levy started all 16 games for the Lions, recording 151 tackles, 2.5 sacks, and 1 interception.
On August 5, it was announced that Levy and the Detroit Lions agreed on a four-year extension.
Levy only played 1 game in the 2015 season due to injury.
In April 2016, DeAndre wrote an article encouraging men and especially professional athletes to take leadership in sexual assault prevention.
As of Week 12 of the NFL season, Levy has played only two of twenty-eight possible games since signing his new contract.
On March 9, 2017, Levy was released by the Lions.