Continuity mistake: When Romeo and his friend drive to the church where Juliet lies. You see that their car is very dirty. But when they arrive at the church the car is all clean. It seems a little strange to clean the car, when they have to hurry, and he was wanted by the police.
Suggested correction: Might have rained somewhere between Mantua and Verona.
Continuity mistake: In the shot after Juliet shoots herself, her left hand which holds the gun falls over her stomach. From the crane shot above, her hand as well as the gun are now on her left side.
Continuity mistake: When Ted and Caroline Montague are searching for Romeo early in the film their car stops once in front of Sycamore Grove, then turns a corner and stops again. In both shots, the background remains the same, as if their car never moved. (00:10:56)
Continuity mistake: When Juliet is bathing in the beginning of the movie we see that she is wearing a silver necklace with a cross. In the next few shots of Juliet after she has exited the bath the necklace has disappeared. (00:16:30)
Continuity mistake: After Juliet has taken the drug to appear dead, her position in bed changes.
Continuity mistake: When Romeo and Juliet are looking at each other through the fishtank, in one shot Romeo's hair is smoothed back and in another it is more in his face.
Continuity mistake: When Tybalt and Romeo fight (just after Mercutio's death) watch Romeo's shirt closely. It is at first dirty and covered in blood then when Romeo is looking up to the sky after shooting Tybalt the shirt looks cleaner with only a few blood stains on it. Also watch the wounds on Romeo's face, the amount of blood on them changes too.
Continuity mistake: When Romeo is writing in his trailer, his necklace chain has both a cross and his wedding ring on it. When he's about to kill himself, he rips off the chain and puts the ring on Juliet's finger. However, the cross is gone.
Factual error: A cigarette cannot ignite petroleum fumes as it does not burn hot enough. This is a common mistake found in a lot of movies.
Continuity mistake: In the beginning gas station scene, Abra, a Capulet, plainly has his sunglasses on before he reveals his SIN grill, and the glasses have been removed a second later as he shouts "BOO" to the Montague Boys.
Continuity mistake: When Romeo and Juliet are in the pool, they near a pool ladder on one side of the pool. When it first shows the ladder, they are about two feet away from it. In the next shot, they are visibly much further.
Continuity mistake: When Juliet tries to run from Romeo in the pool, in the close up shot he's kissing the left side of her neck, but in the next shot he's kissing the right side.
Continuity mistake: At the end of the film Juliet/Claire Danes lifts the revolver to her left temple, in her left hand. After firing the shot and landing, her arm has already fallen before she has.....she lands in an odd position assuming the angle the gun was pointed at, and the original position of her arm.