While shooting the scene where Michael Douglas (Oliver Rose) and Kathleen Turner (Barbara Rose) are sitting in the chandelier, director Danny DeVito pretended to break for lunch while the two actors were 30 feet above ground.
According to director Danny DeVito the first assembled cut of the film ran 3 hours and 4 minutes. It was then cut down to its final length of 1 hour and 56 minutes. Some of the deleted scenes (ca. 20 minutes) can be seen in the trailers and in the deleted scenes montage on the LaserDisc and the Special Edition DVD.
It's popularly rumored that the filmmakers inserted a short shot of the couple's dog into the "pâté" scene after screen testing audience thought it was too cruel. According to Danny DeVito, the dog was always intended to appear; however, it originally wasn't shown until the end of the chandelier scene, and that particular insert was a late addition.
In 1953, Alfred Newman composed and recorded the 20th Century Fox Fanfare "with Cinemascope extension". In 1989, his son, David Newman re-recorded the fanfare for "The War of the Roses" in order to have the last note of the fanfare segue seamlessly into the first note of the opening titles music.
The car that Oliver owns in the movie is a 1960 Morgan Roadster (known to collectors as a Morgan 4/4). The car was really crushed in the film and was purchased by a man named Bill Caruso of Hartford, CT, who restored it with the intention of racing it at Limerock Park, however he died before he could. It was purchased by auto enthusiast Wayne Carini for his show "Chasing Classic Cars".