Ed Wood is depicted as the first to approach pro-wrestler The Super Swedish Angel (Tor Johnson) about appearing in movies. In fact, the real Tor Johnson had been appearing in numerous films since the 1930s.
During the first meeting between Ed Wood and George Weiss where Ed is trying to get funding for Glen or Glenda, Weiss mentions he did a movie entitled Chained Girls, which came out after "Glen or Glenda".
When Lugosi performs on the street in front of a theater, the window marquee for the current feature is for the low budget John Carradine film Half Human, which was not released in the US until December 1958. Lugosi died in 1956.
When Ed Wood first meets Bela Lugosi they are shown in a convertible and as they are driving you can see very modern, steel high tension utility poles along with mercury vapor street lamps that were not in common usage until at least the late 1960s.
When Ed visits Bela Lugosi's home, sidewalk outside his house appears and disappears depending on whether camera is aimed at exterior of house or is depicting Lugosi's view from front door, indicating two different houses were used for scene.
In a screening room, Ed calls back to the projectionist to show the footage again. At which point, the projector (the same projector) immediately restarts although the film has not been rewound and rethreaded.
In the scene where Ed Wood meets Orson Welles, Ed asks him what he's working on. Welles takes a cigar out of his mouth with his right hand. When they cut to a frontal view of Welles, he's holding the cigar with his left hand. When they cut back to a frontal view of Wood, Welles puts the cigar in his mouth with his right hand.
During the "Plan 9" premiere, the footage of Lugosi is shown in its context of that film. However, the narrator's voice heard is the real voice of Criswell and not Jeffrey Jones, the actor portraying him.
When Ed and Kathy emerge from the theatre after the showing of Plan 9, their convertible has been sitting with the top down in pouring rain. Ed opens the passenger door and water pours out of the car, yet when he opens the driver's door seconds later, no water drains from it.
When Bela's morphine addiction becomes apparent, he starts rolling down and buttoning his sleeves so he can put his coat on. He only rolls down the right cuff. The next time the camera is on him, his left sleeve is rolled down, buttoned, and his coat is on. There was not enough time between to accomplish this task.
When Ed is shooting his last footage of Lugosi outside of his house, when the camera is on Lugosi there is a walkway, but when the camera is on Ed, there isn't one. This is only visible in the fullscreen version.
At the start of the world war two theater production Ed can be seen miming the dialog in the background, however when the camera moves to a close up position of him, his left hand has changed positions.
None of the scenes where Ed Wood meets various members of his acting troop ever took place in real life. The film's screenwriters wanted to include such true-to-life stories, but during their research they learned that Wood's friends were so obscure that there was little overall information about them, let alone anything that specific. However, the data that was gleaned in this process turned out to be very useful, as many "fun facts" became part of the final script (for example, Criswell's origin story was eclipsed by the true tale of how he bought his trademark Cadillac from Mae West).
As a sight gag, during the premiere of Plan 9 from Outer Space, Tor Johnson is shown sitting with his wife and two very chubby children. In reality, by the time "Plan 9" was made, Tor's son, Karl, was an adult working as a police officer. Karl had supplied the uniforms and police car for the production of "Plan 9 From Outer Space".
The camera used during dialogue scenes is a Mitchell NC using a notoriously loud 'coffee-grinder' motor. Normally, for dialogue scenes, this camera would have been placed inside a sound-proof 'blimp' housing and used with a sync motor.
When Ed takes Lugosi home after first meeting him, Bela disdainfully says that modern horror movies only show big bugs, giant spiders, giant grasshoppers and the like. But in fact, Hollywood did not begin producing giant-insect films until 1954 - about two years after Wood and Lugosi first met.