According to Florida Highway Patrol, Lucindi Sueann Lane of Kendallville, Ind., was walking south early Saturday along the shoulder of the Howard Frankland Bridge.
She was struck by a car driven by an 18-year-old Florida woman.
FHP officials say Lane, 25, died at the scene.
Neither the driver nor three other teenagers in her car were injured.
It was not immediately clear why Lane was walking across the bridge.
According to an FHP report, alcohol may have been a factor.
The crash remains under investigation.
The Howard Frankland Bridge spans Old Tampa Bay to connect Tampa and St. Petersburg.