Ernie Sims III (born December 23, 1984) is an American former professional football player who was a linebacker and former UCF linebacker coach. He played college football for the Florida State Seminoles and was selected by the Detroit Lions in the first round of the 2006 NFL draft. He also played for the Philadelphia Eagles, Indianapolis Colts and Dallas Cowboys.

A native of Tallahassee, Florida, Sims attended North Florida Christian High School, where he began his high school football career by earning a varsity letter while only in the eighth grade, a feat not often heard of.^[1] A two-way player at running back and linebacker, Sims earned a total of five varsity letters. Playing in Class A, Florida's smallest classification, Sims led the Eagles to four state championships from 1998 to 2001. In his senior year, however, North Florida was eliminated in the region semifinals of the Class A playoffs, losing to Jay 19–14.^[2] As a junior, totaled 180 tackles, 41 tackles for loss, 12 sacks and forced seven fumbles on defense and rushed for over 600 yards and 17 touchdowns as a tailback. During his senior year, Sims registered 133 tackles (73 solo stops), 15 tackles for lost yardage, six forced fumbles, seven fumble recoveries and one blocked field goal attempt from his linebacker position and ran for 1,081 yards on 115 carries for 23 touchdowns as a running back.

Sims earned All-American honors by Parade and USA Today. Rivals.com ranked Sims as not only the top linebacker in his class but as the top prospect in the country.^[3][4] As of 2023^[update], Sims remained the only linebacker ranked atop of the Rivals annual rankings. Recruited by virtually every school in the nation, Sims took official visits to Georgia, Florida, Auburn, Miami (FL), and Florida State. On National Signing Day, Sims chose the Seminoles over the Gators.^[5]

At Florida State, Sims wore #34, a number that was retired in honor of former Seminole football player, Ron Sellers. Sellers gave Sims and the university permission for Sims to wear the jersey number.^[6]

In 2003, as a true freshman at Florida State, Sims played in all 13 games of the season, including the Orange Bowl against Miami (FL), as a back-up outside linebacker. He finished ninth on the team with 42 tackles, and added two tackles for lost yardage, two pass break-ups, three quarterback hurries and a forced fumble. Sims was also one of the Seminoles' top special teams performers. He earned ACC Rookie of the Week for his efforts against Wake Forest, which included a season-high 10 tackles.

As a sophomore, Sims played in all 12 games, and made the starting lineup by the second week. For his exceptional play on the field in 2004, Sims was named to the second All-ACC team and ESPN named Sims to their first-team All-American team. He finished second on the team with a single-season career-high 86 tackles, behind only A. J. Nicholson (88). Sims also recorded a single-season career-high nine tackles for lost yardage, 4.5 quarterback sacks, nine quarterback hurries, five pass break-ups, two forced fumbles and a blocked kick. In three games (North Carolina, Duke, and Florida), Sims recorded double-digit tackles, including a career-high 12 tackles against the Gators. In the Seminoles' 36–3 victory over Virginia, he had nine tackles, a career-high two sacks and a blocked punt. Sims followed that performance with eight tackles, one tackle for lost yardage, a sack and a pass break-up against Wake Forest. Each of those weeks, Sims earned ACC Defensive Back of the Week, as the only player in the ACC to earn the ACC Defensive Back of the Week honors multiple times during the season.

In July 2005, Sims was arrested on charges of battery and resisting an officer, allegedly shoving his then-girlfriend "repeatedly to the ground" during an argument in the parking lot of a FSU residence hall.^[7][8] Expectations for his junior year were high, as The Sporting News and other publications named him to their pre-season All-American teams. Sims had a productive, but not spectacular junior season, starting all 13 games, including the Orange Bowl.

Sims majored in Environmental Studies at Florida State. In January 2006, Sims announced that he would forgo his senior season to focus on a career in the NFL.

On May 29, 2009, Sims married Brooke McGriff, who is pursuing a degree in education at Tallahassee Community College.^[19]

Sims' mother, Alice Sims, formerly Alice Bennett, was an All-American sprinter on the Florida State track and field team from 1980 through 1983.^[20] His younger brother, Marcus Sims, a highly regarded high school running back, announced in February 2006 that he will also play his college football at Florida State before transferring to the University of North Alabama . His father Ernie, Sr. was also a running back at Florida State.

Sims owns a small collection of animals: 5 dogs and 1 type of reptile.^[21] Fox produced a segment for the Lions' game against the Minnesota Vikings in Detroit in 2007 which showcased his pets.

Sims currently resides in his home town of Tallahassee, FL, where he owns his own athletic training facility, called Ernie Sims' Big Hits Performance. He also has his own local sports talk radio show.