The new signing joins from Belgian side Union Saint-Gilloise and will add further European experience to the squad, having played in the Champions League for his former team last season.
Khalaili, who has also won 16 caps at international level, has already set his sights on further success for the Eagles in 2026/27, and beyond.
Trophies are a target for the 21-year-old, who also revealed he has been a long-term admirer of Palace.
