A dentition motion trajectory indicator and a tracing method. The device comprises an intra-oral fixation assembly and an extra-oral motion marking assembly； the intra-oral fixation assembly comprises a lower dentition base support (15), a left-side retention steel wire (1), a right-side retention steel wire (2), and a positioning steel wire (3)； the lower dentition base support (15) is provided on the lingual side of a lower dentition and respectively extends from mandibular incisors to the distal of the last teeth on the left and right sides and clings to lingual mucosa； the left-side retention steel wire (1) and the right-side retention steel wire (2) are symmetrically distributed left and right； the extra-oral motion marking assembly comprises connecting rods (8), an arc-shaped rod (9), an indicator plate, and a plurality of straight cuboid thin rods (12). The dentition motion trajectory indicator uses a personalized intra-oral fixation assembly that is adapted to an individual dentition condition and does not cover an occlusal surface of a maxillary dentition and a mandibular dentition. Therefore, when dentition motion is collected, the occlusal surface of the upper and lower dentitions can be in direct contact, no vertical gap exists between the upper and lower dentitions, and the motion process of the dentition is accurately transferred, without affecting tracing of motion trajectory.L'invention concerne un indicateur de trajectoire de mouvement de dentition et un procédé de traçage. Le dispositif comprend un ensemble de fixation intra-buccal et un ensemble de marquage de mouvement extra-buccal ； l'ensemble de fixation intra-buccal comprend un support de base de dentition inférieure (15), un fil d'acier de retenue côté gauche (1), un fil d'acier de retenue côté droit (2), et un fil d'acier de positionnement (3) ； le support de base de dentition inférieure (15) est disposé du côté lingual d'une dentition inférieure et s'étend respectivement à partir des incisi
