Black was born in Decatur, Alabama, to Jan Gillespie, an office worker, and Larry Black, a museum employee. He has two older siblings and was raised a Southern Baptist. He grew up in Speake, Alabama, played football for the Speake Bobcats, and graduated from high school in May 2001.
Black made his film debut in Kevin Costner's film The War (1994). He subsequently was cast as Caleb Temple in CBS' television series American Gothic, which ran from 1995 to 1996, and in the films Sling Blade, Ghosts of Mississippi, and The X-Files. Later Black starred as Conner Strong in the TV film Flash (1997), which aired on The Wonderful World of Disney; in the movie his character visits a horse every day in hopes of buying it.
Black played a supporting role as Oakley in the historical drama Cold Mountain (2003) and starred as Vernon, an autistic who is a prodigious pianist, in the indie musical drama Killer Diller (2004). Later that year, he starred as Mike Winchell in the football-themed drama film Friday Night Lights (2004), directed by Peter Berg.
Black starred as Nat Banyon in the indie thriller film Deepwater (2005), directed by David S. Marfield; as Chris Kruger in the Gulf War themed drama film Jarhead (2005), directed by Sam Mendes; and as Sean Boswell in the third The Fast and the Furious film, The Fast and the Furious: Tokyo Drift (2006), directed by Justin Lin. He described his part in the latter film as a "fun role".
Black starred as Buddy in the indie drama Get Low (2009), directed by Aaron Schneider; as Jeep Hanson in the bible-themed fantasy thriller Legion (2010); and as Luke Chisholm, a talented young golfer set on making the pro tour, in the indie golfing film Seven Days in Utopia (2010).
He portrayed the Brooklyn Dodgers shortstop Pee Wee Reese in the drama film 42 (2013). Black, having done previous sports films and played sports early in his life, found the filming experience "a lot more enjoyable because you get to reminisce about the days when I used to play, and then you get the experience of being on a team again with the actors and have that camaraderie with the players".
In 2014, Lucas was cast in the NCIS: New Orleans as a NCIS Special Agent Lasalle, a no-nonsense agent with a "work hard, play hard" motto. In 2015, he reprised his Tokyo Drift role in a cameo appearance in the seventh film of The Fast and the Furious series, Furious 7.
In September of 2013, Lucas Black signed a contract with Universal Pictures to repeat his role of Sean Boswell in Furious 8, The Fate of the Furious, Fast & Furious 9 and Fast & Furious 10. It should be noted that Black did not appear in Fate due to "scheduling conflicts" with NCIS: New Orleans, but his contract is still standing, so he will repeat his role as Sean Boswell in the ninth and tenth installments.
Black married Maggie O'Brien, a lawyer, in 2010. They have 2 children.