Tijl De Decker (29 July 2001 – 25 August 2023) was a Belgian racing cyclist.

After switching to the U23s, De Decker first rode for three years for Belgian clubs.

[2] At the Giro Next Gen, he was one of 24 riders disqualified by the jury who determined that the riders had been pulled by escort motorcycles or cars on the final climb up to the Stelvio Pass.

[3] In July 2023, it was announced that De Decker would move from the development team to Lotto–Dstny's UCI ProTeam for the 2024 season.

[4] On 25 August 2023, he died at Antwerp University Hospital from injuries as a result of a training accident in which he collided with the rear of a car in Lier near Antwerp two days earlier.