It's a Wonderful Life is a 1946 American Christmas supernatural drama film produced and directed by Frank Capra. It is based on the short story and booklet "The Greatest Gift" self-published by Philip Van Doren Stern in 1943, which itself is loosely based on the 1843 Charles Dickens novella A Christmas Carol. The film stars James Stewart as George Bailey, a man who has given up his personal dreams in order to help others in his community and whose thoughts of suicide on Christmas Eve bring about the intervention of his guardian angel, Clarence Odbody. Clarence shows George all the lives he touched and what the world would be like if he had not existed.

Although it was nominated for five Academy Awards, including Best Picture, It's a Wonderful Life initially received mixed reviews and was unsuccessful at the box office. Theatrically, the film's break-even point was $6.3 million, about twice the production cost, a figure it did not come close to achieving on its initial release. Because of the film's disappointing sales, Capra was seen by some studios as having lost his ability to produce popular, financially successful films. Its copyright expired in 1974 following a lack of renewal and it entered the public domain, allowing it to be broadcast without licensing or royalty fees, at which point it became a Christmas classic.

It's a Wonderful Life is now considered to be one of the greatest films of all time and among the best Christmas films. It has been recognized by the American Film Institute as one of the 100 best American films ever made. It was No. 11 on the American Film Institute's 1998 greatest movie list, No. 20 on its 2007 greatest movie list, No. 8 on its list of greatest love stories, and No. 1 on its list of the most inspirational American films of all time. In 1990, It's a Wonderful Life was selected for preservation in the United States National Film Registry by the Library of Congress for being deemed as "culturally, historically, or aesthetically significant". Capra revealed that it was his favorite among the films he directed and that he screened it for his family every Christmas season. It was one of Stewart's favorite films.

A modern remake of the film, written and directed by Kenya Barris, is in development at Paramount Pictures as of January 2024.