Tony Danza was born Antonio Salvatore Iadanza in Brooklyn, New York, the elder of 2 sons. He lived with his Sicilian-American family in Brooklyn until they moved to Malverne, NY, when he was a teenager. He attended the University of Dubuque in Dubuque, Iowa on a wrestling scholarship (he majored in History). When he was 18, he got a tattoo on his upper right arm that was based on a design by the comic book artist Robert Crumb; it says "Keep on Truckin'." He married his college sweetheart in 1970 and the couple had a son, Marc (born 1971), together. Danza and his first wife divorced a few years after Marc's birth, and Danza married Tracey Robinson in the late 1980s. He has 2 daughters from his second marriage.

From 1976-1979, Danza was a professional boxer who posted a 9-3 record with all nine wins coming by knockout. He quit fighting when he landed a role as a regular actor on the TV sitcom Taxi.

Danza is probably best-known for his appearances in the TV sitcoms Taxi (1978-1983) and Who's the Boss? (1984-1992).

Danza also starred in the short-lived sitcoms Hudson Street (1995) and The Tony Danza Show (1997, not to be confused with his current talk show). He had a role on the TV drama Family Law from 2000 until 2002.

He was nominated for an Emmy Award for a guest-starring 1998 role in the TV series The Practice. His movie debut was in the comedy The Hollywood Knights (1980), which was followed by Going Ape! (1981). He received critical acclaim for his performance in the 1999 Broadway revival of the Eugene O'Neill play The Iceman Cometh.

Danza now hosts his own TV talk show, The Tony Danza Show, a nationally syndicated program produced each weekday morning in his hometown of New York (where it airs live). On May 9, 2005, during a go-kart race with NASCAR star Rusty Wallace, who was a guest on the show, Danza's kart flipped after Wallace accidentally bumped him. Danza wasn't injured, even though neither he nor Wallace were wearing helmets. Danza returned to go-kart racing on October 20, 2005, to challenge CART driver Danica Patrick, but he was defeated. Tony's daytime talk show is to cease taping in May 2006. The decision to cancel this show is leaving many Italian Americans, like executive officer of the Parents Television Council, Joseph Morisco, very unhappy. Morisco said "There is not much quality on daytime TV these days, and a wholesome show like Tony Danza's really needs to be on. Ay Oh Tony!"

There exist some rumors on the Internet that Danza worked as a pornographic actor early in his career, but these rumors are without foundation. Supposedly, he was the originator of the "Danza slap", a "move" one might see in such a film.

Danza is also an Ordained Minister with the Universal Life Church. He performed a marriage on his talk show.