The film grossed $90,000 its opening weekend, the biggest opening ever at the time.
Merian C. Cooper's first vision for the film was of a giant ape on top of the world's tallest building, fighting airplanes. He worked backward from there to develop the rest of the story.
The trees and plants in the background on the stop-motion animation sets were a combination of metal models and real plants. One day during filming, a flower on the miniature set bloomed without anyone noticing. The error in continuity was not noticed until the film was developed and shown. While Kong moved, a time-lapse effect showed the flower coming into full bloom, and an entire day of animation was lost.
Executive producer David O. Selznick left R.K.O. midway through production of this film. Selznick's last act of business at R.K.O., and probably his biggest contribution to the film, was to write a memo changing the name of the production from "Kong" to "King Kong."
It has been said that this was the first Hollywood film to use a fully symphonic musical score. Some have made the same claim about Bird of Paradise (1932), released earlier. Regardless, Max Steiner, composer for both films, was a forward-thinking man. One of the legends surrounding this film is that director Merian C. Cooper paid Steiner from his own pocket after R.K.O. bosses expressed concern over mounting production costs.