The 62-year-old previously spent over five years at the club between 2017 and 2022. He replaces Michael O’Neill, who opted against taking the job permanently after serving in an interim role last season.
Mowbray returns with vast experience after managing Sunderland, Birmingham and West Brom in recent years.
“Blackburn Rovers is delighted to announce the return of Tony Mowbray as the club's Head Coach,” a statement from the club read.
“Mowbray, who has signed a long-term contract, previously managed Rovers between February 2017 and May 2022, and returns to Ewood Park with a deep connection to the club, our supporters and the wider Blackburn community.
“During his first spell in charge, Mowbray guided Rovers back to the Championship at the first attempt, before establishing the club as a competitive outfit in the division.
“Under his leadership, a number of talented young players emerged through the ranks, while the team consistently challenged in the top half of the table, playing an exciting brand of attacking football.”