The East London club will play in the National League South next season after slipping into the bottom four on a dramatic final day.
A 1-1 draw at Solihull Moors wasn’t enough to keep the Daggers up and a new head coach will take them forward.
Young, the brother of Premier League star Ashley, signed a two-and-a-half-year contract to replace Ben Strevens in January.
But the appointment didn’t work and the club have confirmed a change will be made.
“Dagenham & Redbridge FC can announce that it has today reached an agreement with Manager Lewis Young to terminate his contract with immediate effect,” a club statement read.
“Lewis took up the role as manager in January 2025, having been appointed first team coach in March 2023.
“Despite only one loss in the final 9 games of the season, it was not enough to prevent the club’s relegation to the National League South.
“It was therefore agreed by all parties that a new approach was needed to guide the club back to the National League.
“The club would like to wish Lewis its very best for the future.”