Judon received an invitation to the East–West Shrine Game, but was unable to play after an arthroscopy discovered what was characterized as a " tweaked meniscus ". He was one of sixty-five defensive linemen to receive an invitation to the NFL combine and the first player from Grand Valley State to receive an invite in two years and opted to attend. Judon showed athleticism and strength, finishing top among defensive linemen in the 40-yard dash (5th), bench press (5th), and vertical jump (4th).  On March 15, 2016, he participated at Grand Valley State's pro day, along with four other teammates.  Team representatives and scouts from 26 NFL teams attended his pro day as Judon ran positional drills and opted to stand on his combine numbers. He had an impressive workout and raised his draft stock, receiving much praise from scouts who attended. Throughout the pre-draft process, Judon had private workouts and meetings with the Carolina Panthers, New England Patriots, Arizona Cardinals, New Orleans Saints, Tampa Bay Buccaneers, and Philadelphia Eagles. At the conclusion of the pre-draft process, he was projected to be a fourth round pick by NFL draft experts and scouts.  Although he showed a great combination of strength and athleticism, his fourth round grade was mainly due to teams being skeptical over his ability to transfer his skills to the professional game since he played in D-II in college and concerns over his history of injuries.  He was ranked as the 14th best defensive end prospect by NFLDraftScout.com. 
|Ht||Wt||Arm length||Hand size||40‑yd dash||10-yd split||20-yd split||20‑ss||3‑cone||Vert jump||Broad||BP|
|6 ft 3 in (1.91 m)||275 lb (125 kg)||331⁄ 2 in (0.85 m)||91⁄ 2 in (0.24 m)||4.73 s||1.65 s||2.75 s||4.52 s||7.67 s||35 in (0.89 m)||9 ft 1 in (2.77 m)||27 reps|
|All values from NFL Combine |
The Baltimore Ravens selected Judon in the fifth round (146th overall) of the 2016 NFL Draft.  He was the third edge rusher the Ravnes drafted in 2016, behind Boise State's Kamalei Correa (second round, 42nd overall) and BYU's Bronson Kaufusi (third round, 70th overall).
On May 5, 2016, the Baltimore Ravens signed Judon to a four-year, $2.59 million contract with a signing bonus of $255,736. 
The Baltimore Ravens opted to make Judon an outside linebacker since their 3-4 scheme would better suit him at that position over defensive end. He competed with Terrell Suggs, Elvis Dumervil, Albert McClellan, Za'Darius Smith, Kamalei Correa, Chris Carter, and Victor Ochi throughout training camp for a job as a starting outside linebacker.  Head coach John Harbaugh named him the backup weakside linebacker behind veterans Terrell Suggs and Za'Darius Smith to begin the regular season.
He made his professional regular season debut in the Baltimore Ravens' season-opener against the Buffalo Bills and assisted on one tackle in their 13–7 victory. Judon was inactive for Weeks 3-4 despite playing well in the first three games as the Ravens decided to play Elvis Dumervil who had recovered from his foot injury.  On October 23, 2016, Judon recorded three combined tackles and made two sacks on New York Jets' quarterbacks Ryan Fitzpatrick and Geno Smith in their 24–16 loss. His first career sack on Geno Smith in the second quarter caused Smith to tear his ACL and miss the remainder of the season.  During a Week 14 matchup at the New England Patriots, Judon recorded a season-high five combined tackles in their 30–23 loss. He finished the 2016 season with 27 combined tackles (12 solo), four sacks, and two pass deflections in 14 games and zero starts. Judon played minimally due to a lot of depth at the position and the Ravens staff wanting to develop. 
He competed with Albert McClellan, Terrell Suggs, Za'Darius Smith, Tyus Bowser, Boseko Lokombo, Tim Williams throughout training camp for the vacant starting outside linebacker job left by the departure of Elvis Dumervil in free agency.  On August 26, 2017, he recorded four solo tackles and sacked Buffalo Bills' quarterback Tyrod Taylor in their 13–9 victory. During the sack, Taylor hit his head on the turf and received a concussion from the blow. Judon was named the Baltimore Ravens' starting strongside linebacker, beating out rookie Tyus Bowser, to begin the 2017 season. 
Judon made his first career start in the Baltimore Ravens' season-opener at the Cincinnati Bengals and made one solo tackle and defended a pass in the Ravens' 20–0 victory. During a Week 2 against the Cleveland Browns, Judon recovered a fumble by quarterback DeShone Kizer, that help set up the Ravens' offense on an eventual touchdown scoring drive in the 24–10 victory.  On October 15, 2017, Judon recorded a career-high 14 combined tackles (12 solo) and sacked Chicago Bears' quarterback Mitchell Trubisky twice in their 27–24 loss. On November 19, 2017, he collected seven combined tackles, two sacks, and forced a fumble during the Ravens' 23-0 win against the Green Bay Packers, earning him AFC Defensive Player of the Week.