Marten Elco de Roon (born 29 March 1991) is a Dutch professional footballer who plays as a defensive midfielder for Serie A club Atalanta and the Netherlands national team.

After representing various Dutch youth teams, he started his career at Sparta Rotterdam, and also played for SC Heerenveen in his home country before moving to Italian club Atalanta in 2015.

[16] On 18 July 2017, Middlesbrough confirmed that they paid £8.8 million for De Roon, with Atalanta earning another £900,000 after the midfielder played 30 games for the club.

[18] He once again cemented himself as a starter under Gian Piero Gasperini, and helped Atalanta finish in a historic 3rd place in the 2018–19 season, earning them a spot in the 2019–20 UEFA Champions League group stage.

[21] In the 2023–24 season, he frequently captained his team and marked a milestone by playing his 250th Serie A match in a 3–0 away victory over Empoli, becoming the first foreign player to reach this achievement at the club.

This injury also sidelined him for the Europa League final, where his team secured their first-ever title in the competition with a 3–0 win over Bayer Leverkusen.