Steven Robert Guttenberg (born August 24, 1958) is an American actor, author, businessman, producer, and director. He is known for his lead roles in Hollywood films of the 1980s and 1990s, including Cocoon, Police Academy, Three Men and a Baby, Diner, The Bedroom Window, Three Men and a Little Lady, The Big Green, and Short Circuit.

Guttenberg was born in Brooklyn, New York, the only son, along with his two sisters, of Ann Iris (née Newman), a surgical assistant, and Jerome Stanley Guttenberg, an electrical engineer. His godfather is actor Michael Bell. He had a Jewish upbringing in the Flushing neighborhood of the borough of Queens. In 1976, he graduated from Plainedge High School after his family moved from Queens to North Massapequa. While still in high school, Guttenberg attended a summer program at the Juilliard School and studied under John Houseman.

After graduating from high school, Guttenberg moved to Los Angeles to pursue a career in acting. He made his film debut in 1978 in the drama The Boys from Brazil. His breakthrough role came in 1980, when he starred in the comedy Diner. He then went on to star in a string of successful films, including Cocoon, Police Academy, Three Men and a Baby, and Short Circuit.

In the 1990s, Guttenberg's career slowed down, but he continued to work steadily in film and television. He has appeared in such films as The Lost World: Jurassic Park, The Day After, and Ballers. He has also had recurring roles on the television series Veronica Mars, Law & Order: Criminal Intent, and The Goldbergs.

In addition to his acting career, Guttenberg is also a businessman and producer. He is the co-founder of the production company Guttenflick Pictures. He is also the author of two books, The Guttenberg Bible and The Kids from DISCO.

Guttenberg is married to WCBS-TV reporter Emily Smith. They have been together since 2014 and were married in 2019.