He started his career in the Italian cinema usually playing lead roles in movies directed by his brother Gabriele. His first appearance was in the film But Forever in My Mind (1999), where Muccino plays the lead role of a student participating a school occupation as a protest against the homologation of students. Muccino then starred in movies such as Ricordati di me (2003), Che ne sarà di noi (2004).

After his beginning with his brother, Muccino has appeared in other Italian movies such as Il cartaio (2004, directed by Dario Argento), Manuale d`amore (2005), Il mio miglior nemico (2005).