The 20-year-old has agreed to a five-year contract with the west London club, which includes the option of a further year.
Milambo arrives at Brentford following an impressive 2024/25 campaign in which he made 42 appearances across all competitions for Feyenoord.
A dynamic presence in midfield, he recorded seven goals and eight assists, showcasing both creativity and composure.
He also featured prominently in the UEFA Champions League, playing nine times and contributing three goals and an assist as Feyenoord progressed through Europe's elite competition.
On the international stage, Milambo has represented the Netherlands at Under-21 level under head coach Michael Reiziger.
He made three appearances during the 2025 UEFA European Under-21 Championship in Slovakia, starting in the semi-final where the Dutch fell 2-1 to eventual winners England.
Brentford will hope that Milambo's versatility and technical skill can strengthen their midfield options as they continue to establish themselves in the Premier League.
"We are all very excited by the arrival of Antoni Milambo," said technical director Lee Dykes, via the club's official website.
"The recruitment department have followed Antoni for a few years now and have closely monitored his development at Feyenoord into the first team.
"We believe that Antoni has all the attributes needed to be a very good Premier League player and feel he has the potential to develop his game to a high level here in England.
"Antoni is a skilful, forward-thinking midfield player capable of scoring all types of goals as proven through his youth development phase, in the Eredivisie and in the Champions League.
"I would like to place on record our appreciation to the senior management team at Feyenoord for their assistance with our interest in Antoni and their professionalism throughout the transfer process."
The club's recruitment of young, high-potential talent aligns with their long-term strategy, and Milambo fits that profile perfectly.
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