In the novel, the ape society is technologically comparable to the 1950s or 1960s, with cities, automobiles, televisions, etc., technology left over from the planet's human population. However, the budget could not accommodate the setting, so a more primitive depiction of ape society was used.
In the original script, the female native humans were all bare breasted. This idea was quashed by Fox to appease censors.
Of the original five 'Ape' films, this was the only one to show the Fox logo before the film, and the only one that doesn't feature Natalie Trundy (who plays three different parts in the other four).
One of the biggest stumbling blocks preventing 20th Century Fox from committing to the project was their fear over how the ape faces would appear on screen. Eventually they stumped up $5,000 for a test scene to be shot with Charlton Heston playing alongside the made-up Edward G. Robinson as Dr. Zaius and James Brolin as a character called Mr. Cornelius. The studio was very excited about the results of this test but still delayed green lighting the film for a further six months. It was only after Fantastic Voyage became a hit and showed the viability of science fiction as a genre that "Planet of the Apes" was given the go-ahead, but without Robinson, as he suffered from a weak heart and didn't think he could endure the day-to-day rigors of performing in the ape make-up.
One of the first films to have a major large scale merchandising tie-in. Merchandise related to the film included toys and collectibles, action figures, picture and story books, trading card sets, books, records, comics and a series of graphic novels from Marvel Comics.
Producer Arthur P. Jacobs enlisted several journalists to play background apes. This was a clever way of ensuring that they would write about the film.
Shortly after the astronauts have crash landed Taylor is asked where he thinks they are, having no idea he sarcastically responds, "We're some 320 light years from Earth on an unnamed planet in orbit around a star in the constellation of Orion." In the original novel the story takes place on a planet in orbit around the star Betelgeuse, which is in the constellation of Orion.
Some viewers claim that the windows of the Icarus, when viewed from inside at the beginning, resemble the eyes of the Statue of Liberty.
The "See No Evil Hear No Evil" gag was entirely ad libbed on the set of the day of shooting. It was kept in because people found it amusing when the film was threatening to get too serious.
The apes don't make their first appearance until 30 minutes into the film.
The apes' village is modeled on the work of legendary Spanish architect Antonio Gaudi and the Göreme Valley in Cappadocia, Turkey.
The filming location of the classic final scene has been erroneously thought to be Cabo San Lucas, Mexico, but is in fact Malibu, California. For die-hard fans who want to visit the true location, it is a secluded cove on the far eastern end of Westward Beach, between Zuma Beach and Point Dume. Ignore the wide curving beach by the car park and clamber over the rocks to the east until you get to the quiet, often deserted, little beach surrounded by cliffs. (The Statue of Liberty was an optical effect skillfully achieved with a matte painting blended into a still existing rock structure.)
The final scene with Taylor coming across the Statue of Liberty was suggested by Rod Serling. According to rumor, Pierre Boulle was greatly upset by this ending, but later warmed to it, preferring this new ending over the very different ending he had written. The skeletal remains of the torch appear as "set decoration" in the final episode ofJunkyard of Space.
The fourth astronaut Stewart was originally written as a man.
The make-up team consisted of over 80 make-up artists.
The movie's line "Take your stinking paws off me, you damned dirty ape." was voted as the #66 movie quote by the American Film Institute (out of 100).
The rifles used by the apes are remodeled American M1 Semi-automatic Carbines, primarily used during the Second World War.
The sound effect of the rocket ship hurtling through the atmosphere of the ape planet and then landing in the lake is the exact same sound effect used for the Batmobile in motion from the TV show "Batman" also produced by 20th Century Fox.
The spaceship is inscribed with the acronym ANSA rather than NASA. The meaning of this in-joke is uncertain. The ship itself has been named by fans as the USS Icarus, after Greek mythology's ill-fated flight pioneer.
The spaceship the astronauts crashland in was re-used in Escape from the Planet of the Apes and the short-lived TV series Planet of the Apes.