LaDainian Tarshane Tomlinson (born June 23, 1979) is an American former professional football player who was a running back in the National Football League (NFL) for 11 seasons. After a successful college career with the TCU Horned Frogs, the San Diego Chargers selected him as the fifth overall pick in the 2001 NFL Draft. He spent nine years with the Chargers, earning five Pro Bowl appearances, three Associated Press first-team All-Pro nominations, and two NFL rushing titles. Tomlinson was also voted the NFL Most Valuable Player (MVP) in 2006 after breaking the record for touchdowns in a single season. He played two further seasons with the New York Jets, before retiring. He was elected to the Pro Football Hall of Fame in 2017.

A native of Rosebud, Texas, Tomlinson showed athletic promise while attending University High School in Waco. He was recruited by Texas Christian University (TCU). As a junior, Tomlinson rushed for 406 yards in a single game, a Division I record at the time. As a senior, he earned unanimous All-America honors, and won the Doak Walker Award as the best college running back. TCU retired his No. 5 in 2005, and he was inducted to the College Football Hall of Fame in 2014.

The Chargers selected Tomlinson No. 5 overall after passing on the opportunity to select highly-rated quarterback Michael Vick. A starter in his rookie season, Tomlinson opened his career with the first of seven consecutive seasons with over 1,200 rushing yards, a streak achieved previously only by Eric Dickerson. He became a prolific scorer under Marty Schottenheimer, who coached the Chargers from 2002 to 2006. Tomlinson's output reached a peak in 2006, when he set numerous single-season records, including for most touchdowns scored (31). These feats won him the NFL MVP award, but San Diego suffered an upset defeat in their playoff opener, and Schottenheimer was fired shortly afterwards. Tomlinson became less central to the Charger offense in the following three seasons, and missed time through injury in key games. He was released following the 2009 season, played two seasons with the Jets, and retired.

Tomlinson was named to five Pro Bowls (2002, 2004–2007), was a first-team All-Pro three times (2004, 2006, 2007), and won consecutive rushing titles in 2006 and 2007. At the time of his retirement, he ranked fifth in career rushing yards (13,684), fifth in yards from scrimmage (18,456), second in career rushing touchdowns (145), and third in total touchdowns (162). Tomlinson also threw seven touchdown passes and ranks second behind Walter Payton (eight) for non-quarterbacks in the Super Bowl era. Tomlinson had his No. 21 retired by the Chargers in 2015 and was inducted into the Pro Football Hall of Fame in 2017, his first year of eligibility.

Tomlinson is often known by his initials, L.T.. He works as an analyst on the NFL Network, and also serves as a special assistant to the Chargers' principal owner, Dean Spanos.