Goofs

Shichiroji throws a spear out the door of Rikichi's hut in anger, it lands in parallel with the door. Later, after Kikuchiyo's outburst, he runs outside and picks the spear up; however, it's now laying sideways compared to the door.

In the closing moments of the final battle, the bandits fire two musket shots only seconds apart. It is clear from the plot that at that point they possess only one musket. The black powder muskets of the age required much more time to reload. This error was pointed out in the commentary of the deluxe DVD edition.

When Gorobei is first seen, Katsushiro is about to test him (by hiding behind the entrance). Gorobei notices Katsushiro's shadow on the entrance and laughs, realizing that someone is hiding there. However, the position of his own shadow reveals that the sun is on the other side. Therefore, it was impossible for him to notice Katsushiro's shadow from where he was standing; It would be cast backwards into the room, not towards the entrance.

The dead bandit blinks twice when Kikuchiyo takes his forehead protector.

During the first scene when the people in the village are discussing what to do with the bandits, it's visible that they are wearing bald-wigs.

In the battle scene samurais keep cutting down bandits with their swords one after another but there is never any blood on their swords even after a very bloody battle with many casualties. There is no blood shown in this movie in any of the battle scenes and swords are always clean throughout the movie.

When the samurai are giving battle advice to the peasants, who sit around them forming a circle, the camera does a rather wide circle shot of them. A dolly track can be seen behind the seated peasants.

When Gorobei is asking Heihachi to join the team, he asks "Do you feel like cutting down 30 bandits?" although he knows that there are 40 bandits. (This is not a translation error, the line is "30 bandits" in all translated versions of the movie.)