Prioleau played college football at Virginia Tech. As a freshman, he appeared in 11 games on special teams and as a reserve cornerback and finished that season with 24 tackles. As a sophomore, he started every game at rover position, appeared in 809 total plays and finished with 71 tackles. As a junior, he was named first-team All-Big East and third-team All-America by Sporting News. He posted 81 tackles and two sacks that year. As a senior, he started every game for the defense that led the Big East with only 12.9 points per game allowed. He finished with 61 tackles and two interceptions.
Prioleau was drafted in the 1999 NFL Draft by the San Francisco 49ers. While with the 49ers for the 1999 and 2000 seasons, Prioleau started 11 of 28 games he played in as a safety and corner, accumulating 81 tackles and one interception.
Buffalo Bills
Prioleau signed with the Buffalo Bills on November 7, 2001 but was inactive for first three games after joining the team. Prioleau was impressive when he saw action in the final six games. In his first full season with the Bills in 2002, Prioleau started all 16 games at free safetyfor the first time in his NFL career. He finished fifth on the team with a career-best 86 tackles and also had 10 stops on special teams. In 2003, Prioleau appeared in all 16 games with six starts in his second full season in Buffalo. He posted 37 tackles,.5 sacks, four quarterback pressures and one forced fumble. In 2004, Prioleau played in all 16 games with two starts in final season with Buffalo. He totaled 37 tackles on the year.
Washington Redskins
In his first season with the Washington Redskins in 2005, Prioleau played in 15 games, had 43 tackles, three sacks, and a forced fumble. On opening day2006, while playing in a game versus the Minnesota Vikings, Prioleau injured himself during the opening kickoff and spent the rest of the season on Injured reserve.
Jacksonville Jaguars
On April 29, 2008, Prioleau signed with the Jacksonville Jaguars.
Prioleau signed a one-year deal with the New Orleans Saints on March 26, 2009. He re-signed with the Saints on March 5, 2010 and again on July 29, 2011. He was released on September 3, 2011.
Personal life
Prioleau and his wife, Alicia, have three sons: Pierson Jalen, Parker Jayden and Pace Jordan.