LaFell attended Lamar High School in Houston, where he played football, basketball and ran track. He was coached by Tom Nolen. In football, LaFell caught 46 passes for 1,116 yards and 16 touchdowns as a senior. Also starring on special teams, he returned punts of 65 and 58 yards for touchdowns. LaFell was a member of the Houston Chronicle Top 100 and named first-team All-Greater Houston Area in 2004. In basketball, LaFell was a standout point guard. In track & field, LaFell competed in the high jump event.
After redshirting his initial year at LSU, LaFell saw action in 11 of the Tigers’ 13 games in 2006. His first career play was a 58-yard touchdown reception against Louisiana-Lafayette in week one. On the year, LaFell caught five passes that went for 140 yards and two touchdowns. He received Freshman All-SEC honors by the coaches.
In 2007, LaFell played in all 14 games with nine starts. He ranked first on team in receiving yards (656) and second in receptions (50), while catching four TD passes and averaging 13.1 yards a reception. LaFell helped LSU to win the BCS National Championship that year.
As a junior, LaFell emerged as one of the top receivers in the country, as he caught 63 passes for 929 yards and eight touchdowns. He ranked No. 2 in the SEC in yards per game with 71.5 per contest and was No. 3 in the league with 4.8 receptions per contest. LaFell subsequently earned First-Team All-SEC honors by the Associated Press.
On April 23, 2010, LaFell was selected by the Carolina Panthers in the third round, 78th overall. Despite not starting over Steve Smith and David Gettis, he gradually gained playing time, eventually taking the #3 slot at receiver. He recorded his first NFL touchdown in Week 8 against the St. Louis Rams, a 17-yard pass from Matt Moore.
He finished the season with 38 catches for 468 yards; his longest catch was of 44 yards. He also gained 60 additional yards on the ground, all of which came on a single end-around play in week 17 against the Atlanta Falcons, his longest gain of the season.
LaFell set a Carolina Panthers franchise record on Christmas Eve in 2011 with a 91-yard touchdown catch from rookie QB Cam Newton. It was the longest pass play in Panther history.
On March 15, 2014, LaFell signed a three-year, $9 million contract with the New England Patriots. He chose to wear #19 because friend and former teammate Ted Ginn, Jr. wears the same number. Against the Chicago Bears in week eight, LaFell recorded a career-high eleven catches for 124 yards and a touchdown. In 2014, LaFell had his most prolific season to date, recording 74 catches for 953 yards and 7 touchdowns. LaFell would help the Patriots finish 12-4. In the Divisional round against the Baltimore Ravens with the Patriots down 31-28, Lafell caught the game winning touchdown to help the Patriots defeat the Ravens 35-31. In Super Bowl XLIX, LaFell had 4 catches for 29 yards and the first touchdown of the game as the Patriots defeated the Seattle Seahawks 28-24. LaFell missed the first five games of the season in 2015 before returning in New England's 30-23 win over the New York Jets. He had two catches for 25 yards in the win, which pushed the Patriots to 6-0.