Widmark first appeared in movies in 1947's Kiss of Death (in which he giggles as he pushes a wheelchair-bound old woman (played by Mildred Dunnock) down a flight of stairs), which started his seven year contract with 20th Century Fox. He was nominated for the Academy Award for Best Supporting Actor for the performance. Widmark's character in this film was the inspiration for the song, "The Ballad of Tommy Udo" by the band Kaleidoscope.

Widmark became so popular so fast that it was only two years later that he had his handprints cast in cement at Grauman's Chinese Theater. In the intervening two years, he had appeared in Slattery's Hurricane, Down to the Sea in Ships, Yellow Sky, Road House and The Street with No Name.

His first wife, Jean Hazlewood, to whom he was married from April 5, 1942 until her death on March 2, 1997 was the mother of his daughter, Anne Heath Widmark who married baseball legend Sandy Koufax on January 1, 1969. He is happily remarried to Henry Fonda's third ex-wife, Susan Blanchard since September of 1999.

Other starring roles include:

Night and the City (1948) Panic in the Streets No Way Out Don't Bother to Knock Halls of Montezuma (1951) Destination Gobi Pickup on South Street Take the High Ground! The Cobweb (1955) Backlash Run for the Sun (1956) The Last Wagon Warlock The Alamo The Secret Ways Two Rode Together (1961) Judgment at Nuremberg (1962) How the West Was Won (1962) The Long Ships (1963) Cheyenne Autumn (1964) The Bedford Incident (1965) The Way West (1967) When the Legends Die Murder on the Orient Express (1974) Coma (1978) Madigan (1968) (Widmark also starred in the Madigan' television series, which was based on this movie). For his contribution to the motion picture industry, Richard Widmark has a star on the Hollywood Walk of Fame at 6800 Hollywood Boulevard. In 2002, he was inducted into the Western Performers Hall of Fame at the National Cowboy & Western Heritage Museum in Oklahoma City, Oklahoma.