The spider that portrayed the giant tarantula later appeared in L'Homme qui rétrécit (1957) as the spider threatening the shrinking man.
Professor Gerald Deemer, played by Leo G. Carroll, predicted that by the year 2000, the human population will be 3.6 billion. In fact, it was almost double that by then.
Second uncredited theatrical movie of Clint Eastwood (Jet Squadron Leader). His first being La Revanche de la créature (1955).
Leo G. Carroll and this movie's title, "Tarantula", were mentioned in the song "Science Fiction Double Feature" from The Rocky Horror Picture Show (1975).
The tarantula was an actual live spider. Air jets were used to make it move in the desired way over a miniature landscape.