He is known for his role as Peter Petrelli on the NBC television series Heroes.
At 18 years of age, Ventimiglia started auditioning, booking jobs, and working his way up.
His first starring role was as a gay teenager in Must Be the Music, a short film released as part of Strand Releasing's Boys Life 2.
From there, Ventimiglia studied at UCLA before landing a role on The Fresh Prince of Bel Air.
He has guest starred on such television series as CSI: Crime Scene Investigation, Sabrina, the Teenage Witch, Law and Order: Special Victims Unit and Boston Public.
He had the part of the main character, Jed Perry, in the short-lived FOX TV series, Opposite Sex.
From 2001 to 2004, Ventimiglia played brooding teen Jess Mariano on Gilmore Girls; he was introduced in the second season as a main cast member.
In season four he dropped down to a guest star/recurring cast member, and he came back for two episodes in season six.
He stars as Ian Mitchell in the Crackle original series Chosen as well as Sean Bennigan on The Whispers.
The youngest of three children, he has two older sisters, Leslie and Laurel.
He explained in an interview with USA Today that his "crooked mouth" is a result of dead nerves on the left side, which cause that side to remain immobile, much like, incidentally, actor Sylvester Stallone, with whom he worked in Rocky Balboa.
Ventimiglia attended El Modena High School in Orange, California, where he wrestled, acted in drama productions and held the office of president in student government. At eighteen years of age, Ventimiglia studied at the American Conservatory Theater for their summer program.