Born July 10, 1997, in Cowan, Tennessee, Bennie Jauan Jennings attended Blackman High School in Murfreesboro, Tennessee, where he played quarterback before converting to wide receiver in college. A four-star recruit, he committed to the University of Tennessee, where he played for the Volunteers from 2015 to 2019 under head coaches Butch Jones and Jeremy Pruitt. Despite being dismissed from the team in 2017 after a wrist injury and a disciplinary issue, he was reinstated by Pruitt and earned a medical redshirt for the lost season. Jennings made the most of his second chance, finishing his collegiate career with 146 receptions for 2,153 yards and eighteen touchdowns.

The San Francisco 49ers selected Jennings in the seventh round with the 217th overall pick in the 2020 NFL Draft, a selection that would prove to be one of the great late-round values of that draft class. Strengths include exceptional physicality at six feet three inches, superb contested-catch ability, toughness after the catch, and unique versatility as both a receiver and passer that makes him one of the most difficult matchup problems in the league.

His collegiate heroics foreshadowed his NFL career. In 2016 against rival Georgia, Jennings hauled in a game-winning forty-three-yard Hail Mary from quarterback Joshua Dobbs with no time remaining to stun the Bulldogs 34-31. During a critical Week 3 road game against the Rams in 2024, with most of San Francisco's top receivers sidelined by injury, Jennings delivered an eleven-reception, 175-yard, three-touchdown performance that announced him as the team's primary receiving threat. In Super Bowl LVIII against the Kansas City Chiefs, Jennings became just the second player in Super Bowl history to both throw and catch a touchdown in the same game, joining Nick Foles, throwing a twenty-one-yard scoring strike to Christian McCaffrey and catching a touchdown pass himself.

Jennings has accumulated 210 career receptions for 2,581 yards and twenty-two touchdowns across seventy-five regular-season games. His 2024 season total of seventy-seven receptions for 975 yards represented career highs in both categories, ranking him among the top performers at his position that year despite not being considered a featured starter entering the season.