Novello is best known for his work on NBC's Saturday Night Live, from 1977 until 1987, as the character "Father Guido Sarducci".
Novello has appeared as "Sarducci" on many television shows since then, inclduing Married with Children, Blossom, It's Garry Shandling's Show, and Square Pegs.
Novello made newspapers around the world when he visited the Vatican wearing the full Father Guido Sarducci costume and was arrested by the Swiss Guards for "impersonating a priest". The charges were later dropped.
Novello started his career as a performer on The Smothers Brothers Show in 1975.
In the early 1980s, Novello produced SCTV, a Toronto-based comedy show, which starred Martin Short, Joe Flaherty, John Hemphill, Eugene Levy, Andrea Martin, and Mary Charlotte Wilcox.
In the 1970s Novello started to write letters to famous people under the pen name of Lazlo Toth (name taken from that of a deranged man who vandalized Michelangelo's Pieta in Rome). The letters, designed to tweak the noses of politicians and corporations, were full of deliberate misstatements of fact and inside jokes. Many of these letters received serious responses; Novello sometimes continued the charade correspondence at length, with humorous results. The letters and responses were published in the books The Lazlo Letters (ISBN 1563052857) and Citizen Lazlo! (ISBN 1563051826).
Novello co-wrote the unfilmed script for "Noble Rot", with John Belushi.
In 1990, Novello portrayed "Dominic Abbandando" in the film, "Godfather: Part III".
Don Novello currently resides in Marin County, California. In 2003, he filed papers to enter the 2003 California recall election, but failed to collect enough valid signatures to qualify for the ballot.