He was born Rodney Stephen Steiger to Lutheran parents in Westhampton, New York. He ran away from home at age sixteen to join the United States Navy during World War II, where he saw combat on destroyers in the Pacific. After the war, he returned to New Jersey and joined a drama group before studying drama full-time under Lee Strasberg and Elia Kazan at The Actor's Studio.

Steiger appeared in over 100 motion pictures. He won the Academy Award for Best Actor in a Leading Role for his portrayal of Sheriff Bill Gillespie in In the Heat of the Night (1967) opposite Sidney Poitier.

He was nominated for the Academy Award for his roles in On the Waterfront (1954) and The Pawnbroker (1965).

Steiger had five wives, the late actress Sally Gracie (married 1952-divorced 1958), actress Claire Bloom (married 1959-divorced 1969), Sherry Nelson (married 1973-divorced 1979), Paula Ellis (married 1986-divorced 1997) and actress Joan Benedict (married 2000-his death 2002). He had a daughter, opera singer Anna Steiger, by his marriage to Bloom.

He was offered the title role in Patton but turned it down because he did not want to glorify war. The role was then given to George C. Scott, who won the Oscar. Steiger called this refusal his "dumbest career move." He also turned down The Godfather.

He died in Los Angeles of pneumonia and complications from surgery for a (presumably malignant) gall bladder tumor at the age of 77. He is interred in Forest Lawn Memorial Park at Hollywood Hills in Los Angeles, California.

Rod Steiger has a star on the Hollywood Walk of Fame at 7080 Hollywood Boulevard in Hollywood, California.