Factual error: When Henry and Karen are racing to Karen's mother's house when the helicopter is following them, the driveway Henry pulls up in has a 1982 or newer Pontiac Bonneville, but the scene was supposed to take place in 1980.

Continuity: When Paulie and the others are in prison and preparing dinner, there is a vase on the table where they will eventually eat dinner. The vase is filled with fresh basil at the beginning of this scene but disappears and re-appears throughout the scene.

Continuity: In the scene where the guys go to Florida to "feed the guy to the lions," the lion first shown is a male with a huge mane. When seen upside down the 1st time it's the male, but the second time it's a female, no mane, slightly smaller, lion. They never show more than 1 lion in the pen, either.

Continuity: In the scene when Spider is killed by Tommy, Jimmy is with his arms wide open just the instant before Tommy pulls the trigger. But in the next shot, when Tommy fires the gun, Jimmy is with his arms down.

Audio problem: In the bar scene where Tommy gets enraged at Billy Batts, at one point Billy says "Salute Tommy" but his lips does not move.

Continuity: When Henry has just showed De Niro the guns and he's in his car, you see him light up a cigarette. When the shot changes the cigarette has vanished.

Continuity: Henry and Jimmy are eating in a diner waiting for word about Tommy being "made". When Jimmy goes outside to make the call to find out, there is a car parked outside the diner, at this point, the car's window is open. When Jimmy starts kicking over the phonebooth and Henry comes outside to join him, the car's window is closed.

Audio problem: In the scene where Tommy shoots Spider in the foot we hear 7 gunshots from what appears to be a 6 shot .38 revolver.

Continuity: In the scene where Jimmy and Henry are leaving a diner after Morrie got whacked, Henry asks Jimmy "Well, what the f%&. do you want me to tell Belle?" (referring to Morrie's disappearance). Jimmy says "Who gives a f%&. Tom? Tell her he ran off with some broad. What do you care about her?" Jimmy calls Henry "Tom", then seems to look off screen right. It's as if he realized his mistake and was looking for Marty Scorsese to say "CUT"

Continuity: After Karen has been with her girlfriends, she is talking to Henry about what is going to happen if he gets killed, at that point Henry is folding his pants by the closet, when the camera angle switches he is suddenly very quick on his knees in front of Karen.

Continuity: While Henry and Jimmy are beating up the guy in the car, Henry is holding a gun up to the guy's face. A few times during the scene, it changes back and forth from the gun pressed right up against his face to the gun a little away from his face.

Factual error: When Henry Hill is at the doctor's office, the doctor gives him 10 mg Valium pill which is brown. In reality, Valium 10 mg is light blue and has a "V" shaped hole in the center of it.

Continuity: When Ray's girlfriend is showing off her apartment to her two girlfriends they walk down the hall to the bedroom. The camera then changes to them entering the bedroom door and the order of girls has changed.

Factual error: When Henry is being followed by the helicopter, he almost slams into another car. Henry's car has a brake light in the back window, but they didn't start that until the mid 80's at the earliest.

Continuity: When Henry and his girlfriend enter the Copacabana avoiding waiting in the line, their way through the catacombs of the nightclub is prolonged artificially because they exit the kitchen by the same door they entered it. The scenery is changed a bit by moving some racks and a curtain but you can tell it's the same because they pass the same firehose on the wall twice.

Continuity: When Karen is at the the Hostess party, and Jimmy Conway's wife is talking about Jeanie's family, if you look at the lady she's applying make up to, she crosses begins to herself twice. One when the camera is one her and Jimmy's wife, then again when the camera is just on her.