Continuity: There is a scene at an airport where Mel Brooks is approached by a man claiming to be a FBI agent or something like that. In the next shot inside the bathroom you can see the boom microphone from the top of the screen.
Great sites
Mistakes
When Mel Brooks is singing the song "High Anxiety" to a bunch of people in the dining room, near the end of the song he sings about two words and his mouth is clearly not moving. See more...
High Anxiety mistakes
Continuity: Madeline Kahn and Mel Brooks are in a hotel room in San Francisco. She is smoking a cigarette which grows shorter as the scene progresses. After cutting away and then back to her, the cigarette is long again.
Other: When Mel Brooks is singing the song "High Anxiety" to a bunch of people in the dining room, near the end of the song he sings about two words and his mouth is clearly not moving.