Christian Nyby (September 1, 1913–September 17, 1993) was an American television and film director.

Born in Los Angeles, California, he started his career as a film editor in the 1940s. During this period, he worked on four films for famous director Howard Hawks, of which one (Red River) led to an Academy Award nomination. He began his career in the carpentry division at the studios, worked his way up to editor, then got the chance to direct his first film in 1951. The Thing from Another World (or The Thing as it is more commonly known) was an instant success attributed mostly to the producer Howard Hawks. Nyby went on to have a prolific television and movie directing career, from the 1950s to the 1970s. He directed episodes of almost every major television show of the period, from Perry Mason, Bonanza, The Twilight Zone, to Kojak.

Nyby is the father of Christian I. Nyby II, a prolific television director in his own right.

Christian Nyby, the television and movie director who achieved acclaim as a film editor before moving into the director's chair, was born on September 1, 1913, in Los Angeles, California. He made his reputation as a cutter during the 1940s, when he worked with the great helmer Howard Hawks, winning his sole Academy Award nomination for the editing of Hawks' classic Western Red River (1948) (1948). Nyby first collaborated with Hawks as an editor at Warner Bros., on the director's adaptation of his friend Ernest Hemingway's novel To Have and Have Not (1944) (1944). He edited Big Sleep, The (1946), both the original 1944 version and the recut version that put more emphasis on stars Humphrey Bogart and Lauren Bacall that was released in 1946. In a real-life scenario similar to Robert Wise (I)'s cutting of Orson Welles's second masterpiece, Magnificent Ambersons, The (1942), Nyby had to cut Red River (1948) on his own when director/producer Hawks had to go to Europe to complete another assignment. Nyby had to shorten Hawks' original cut, and also eliminate scenes that producer Howard Hughes (I) thought plagiarized his own Western Outlaw, The (1943), which Hawks had worked on. Though the film became regarded as a genre classic in the original Nyby cut, the original cut that Nyby had made under Hawks' supervision survived and was released during the 1960s, further burnishing the reputation of the film. Nyby moved to the directors' chair for producer Hawks for the sci-fi movie Thing from Another World, The (1951). Although The Thing is rightly regarded as a classic, credit for the direction of the film generally is attributed to Hawks as he reportedly was on the set everyday as the producer, and the film bears his "auteurist" stamp. Furthermore, Nyby's subsequent directorial output in film and on TV was mediocre, unlike this, his debut. Some believe the Hawks was ashamed to put his name on such a lowly genre piece (sci-fi was despised, critically, until Stanley Kubrick's 2001: A Space Odyssey (1968) a generation later, and that film, one of the great classics of cinema, initially engendered hostile reviews from critics). Another theory is that Hawks helmed the film himself but let Nyby, who was on the set learning the ropes of direction, take the director's credit on the picture to receive membership in the Directors Guild. Whatever the truth, "The Thing" -- Nyby's greatest accomplishment as a director -- generally is credited to Hawks in fact or in spirit, so much is his style evident in the picture. Nyby went on to direct B-movies such as the uninspired ode to the Marine Corps and battlefield sacrifice First to Fight (1967) (1967) and episodic television, never again showing the promise he had as director of "The Thing." He died on September 17, 1993, two weeks after turning 80 years old.