Continuity mistake: When Harry and Cedric are transported to the cemetery, the Triwizard cup lands on the grassy slope, well beyond the Riddle monument, with its luminescent top facing away from the cauldron area. During Priori Incantatem, three shots after Voldemort exclaims, "He's mine!" the cup lies on the corner of the Riddle monument's stone base and it faces the opposite way. The cup is back up on the grassy area in the following shots. (01:19:00 - 01:28:40)
Continuity mistake: After Wormtail performs the Avada Kedavra curse and then raises the "bone of the father," he places Voldemort's wand inside the left side of his coat, before he slices off his right hand. When Voldemort says, "My wand Wormtail," Wormtail retrieves the wand from the right side of his coat. (01:56:00 - 01:57:40)
Continuity mistake: In the cemetery, just after Voldemort shouts, "He's mine!" when he faces off with Harry during Priori Incantatem, in this specific overhead wide shot, which is directly over Cedric's body and the Triwizard Cup in the foreground, the Cup is only a couple of feet away from Cedric's feet; whereas in a previous wide shot, when Voldemort says, "Here you stand before me as though it were only yesterday..." both the trophy and Cedric's body are seen at the top of the screen (with the Riddle monument in between), and the Triwizard Cup is quite a distance away, at least 4-5 feet, from Cedric's body. (02:03:30)
Visible crew/equipment: After Beauxbaton's entrance into the dining hall, Fleur bows in a close-up with the wood platform directly behind her, and then Dumbledore kisses Madame Maxime's hand. In the next shot, when Dumbledore quickly runs up onto the platform to introduce Durmstrang, there is a white mark on the wood which he promptly stands on. This mark is not on the platform in either the previous or following shots. (00:17:40)
Continuity mistake: When HRH are in the Great Hall, there is a toast caddy on the table in front of Harry. Certain pieces of toast disappear and reappear or rearrange themselves, depending on the camera angle, from the start of this scene when Harry dribbles on himself, through Ron's reaction to his dress robes.
Continuity mistake: When Dumbledore is about to introduce the other schools and Filch comes running through the great hall, he runs past Ron twice on his way up to the podium. The first time Ron is sitting up and his head turns as Filch runs past. As Filch continues to run, he passes Ron again, who this time has been lying his head on his arms on the table, and sits up as Filch runs past. The people near Ron also change and keep changing. (00:16:00)
Continuity mistake: After the Yule Ball, when Neville walks into the dormitory, his shoes hang round his neck by their laces. While he says, "You alright Harry?" in Neville's first close-up his black collar lies flat, the shoes' laces hang round his white shirt and the heels touch. In the second shot his black collar is flipped up around his neck, the shoes' laces hang round the black collar and heels are about four inches apart. Then, in the third shot it reverts back, as in the first shot.
Continuity mistake: Seamus is sitting by Ron when Beaxbatons Academy and Durmstang are being introduced in the Great Hall. Then, when Mad-Eye Moody comes in and Hermione is telling them who he is, Seamus is suddenly sitting by her, across the table from Ron. Ginny also moves - she's initially by Hermione, then when Seamus suddenly takes her place, she's now sitting further down the table.
Revealing mistake: Aboard the Hogwarts Express, when Harry stands beside the open window and sends Hedwig off with the letter for Sirius, surely his hair and clothes would be wildly moving about, because of the strong wind from the fast moving train.
Continuity mistake: After Draco is changed back into a boy (from a ferret), Moody sticks his staff into the ground before he chases Draco around the tree. Initially his staff is leaning at a 45° angle, but when Draco comes around the tree and leaves the courtyard the staff is standing upright, at a 90° angle. (00:14:25)
Continuity mistake: During the Priori Incantatem, Harry is shown using both hands to hold his wand steady. The very next shot, however, shows him holding with just one hand, then his other hand comes up to grasp the wand as well. (02:03:10)
Continuity mistake: When Fred or George passes the note to Ron in the Great Hall, encouraging him get a date before all the good ones are gone, the position and style of writing on the note changes between shots. The number of lines changes from four to three and the words are written lower on the paper when Ron reads it.
Continuity mistake: In the maze, when Cedric says, "For a moment there I thought you were gonna let it get me," the tear on his shirt, at his right shoulder, is directly on the seam and quite frayed. At the cemetery, when Harry says, "Cedric, we have to get back to the cup. Now!" the tear is not on the seam, and it's smooth with blackened edges. Back in the maze, when Amos approaches his son's body, the tear differs yet again. The dirt on Cedric's shirt changes as well. (01:58:20 - 01:59:40)
Audio problem: At the cemetery, as Harry lies on the ground, when Voldemort leans over him and says, "If they speak of you they'll speak only of how you begged for death," in the shot facing Harry, before Voldemort continues to speak, his mouth still moves, though nothing is heard. (01:27:25)