Continuity: In the scene where Rooster is going down inside the well to bring up the girl, he draws and shoots a rattle snake. When he gets to her he is not wearing a gunbelt, and when he gets back to the top, he is wearing it again.

Other: Throughout most of the film, Mattie Ross' gun is correctly shown to be a Colt's Dragoon .44 caliber revolver. However, in the scene where Tom Chaney is looking down at her from the top of the well into which she had fallen, the gun in his hand is a Colt's Model 1860 Army. Presumably, when he, too falls into the well after being shot by Marshall Cogburn, the gun goes with him. When Cogburn retrieves the weapon before helping Mattie out of the pit, the gun is once more a Colt's Dragoon.

Factual error: In the scene where John Wayne is getting the girl out of the snake pit, there is a valley behind him and another mountain across the valley. In one shot, on that mountain in the background you can see a car pulling a house-trailer along a road.

Continuity: After Kim Darby declines the coffee, John Wayne puts his empty plate in the middle of the table. Immediately in the next shot, the plate is back in front of him with some scraps of food still on it.

Continuity: At the dinner scene when Mattie Ross is trying to obtain Rooster Cogburn's services, Rooster clears the table, and in the next scene he re-clears the table by pushing everything aside to play cards with Chin Lee.

Factual error: Campbell is armed with what is described by Wayne as a "buffalo gun", a large bore rifle known for its power and substantial recoil. Campbell shoots a wild turkey with the gun and causes the meat to be severely damaged. Wayne comments, "Too much gun" emphasizing the power of the gun. However, when Campbell shoots the turkey with this "buffalo gun" there is no visible recoil.

Continuity: Near the end of the movie, after Rooster and Mattie's horse has collapsed, Rooster begins to carry Mattie. You can see that Mattie's blouse has come untucked from her skirt. However, once Rooster has acquired the wagon, Mattie is laid across his lap and her blouse is now tucked back into her skirt.

Continuity: In the scene when John Wayne puts his reins between his teeth and his rifle in his right hand and his pistol in his left, at one point they switch hands.

Factual error: There are no snow-capped mountain peaks anywhere near Ft. Smith, Arkansas. They appear to have chased Ned Pepper all the way to the Rockies, 500 miles or more away.