An apparatus for generating dental data for manufacturing an aligner, the apparatus comprising: a database that is configured to store and manage pre-alignment and post-alignment contour data and guide information, with respect to generated alignment data, a dental-data management program that is configured to provide interfaces for functions of units and modules of the apparatus, a dental-data generation unit that is configured to generate data on an alignment target tooth in multiple stages based on a current arrangement of teeth of a patient, and a dental-data generation module configured to generate 3D data on an alignment target tooth, wherein the dental-data generation unit includes a preprocessing module that includes a first module that is configured to receive data on a current state of the teeth of the patient from a scanner that scans the current state of the teeth of the patient, a second module that is configured to generate a state of the teeth of the patient and the vicinity of the teeth as 3D data, based on the data received from the scanner, a third module that is configured to set a central point (322a, 352a) for dental movement in the 3D data, a fourth module that is configured to set each central reference for a crown, a buccal surface, and a lingual surface of the tooth in the 3D data, and a fifth module that is configured to set a reference for a dental root point in the 3D data, characterized in that the third module sets the central point (322a, 352a) for dental movement by recognizing a tooth, an alveolar bone that encloses the tooth, and a gingiva (210a, 303) that encloses the alveolar bone, and in that the central point for dental movement is set with respect to a single-rooted tooth with one root to be positioned at a distance of 40% to 42% of the root of the tooth enclosed by an alveolar bone downward from the top of the alveolar bone, and in that the central point for dental movement of which is set with respect to a multi-rooted tooth to be positioned at a distance of between 1 and 2 mm downward from the furcation from which the root of the tooth bifurcates. a database that is configured to store and manage pre-alignment and post-alignment contour data and guide information, with respect to generated alignment data, a dental-data management program that is configured to provide interfaces for functions of units and modules of the apparatus, a dental-data generation unit that is configured to generate data on an alignment target tooth in multiple stages based on a current arrangement of teeth of a patient, and a dental-data generation module configured to generate 3D data on an alignment target tooth, wherein the dental-data generation unit includes a preprocessing module that includes a first module that is configured to receive data on a current state of the teeth of the patient from a scanner that scans the current state of the teeth of the patient, a second module that is configured to generate a state of the teeth of the patient and the vicinity of the teeth as 3D data, based on the data received from the scanner, a third module that is configured to set a central point (322a, 352a) for dental movement in the 3D data, a fourth module that is configured to set each central reference for a crown, a buccal surface, and a lingual surface of the tooth in the 3D data, and a fifth module that is configured to set a reference for a dental root point in the 3D data, characterized in that the third module sets the central point (322a, 352a) for dental movement by recognizing a tooth, an alveolar bone that encloses the tooth, and a gingiva (210a, 303) that encloses the alveolar bone, and in that the central point for dental movement is set with respect to a single-rooted tooth with one root to be positioned at a distance of 40% to 42% of the root of the tooth enclosed by an alveolar bone downward from the top of the alveolar bone, and in that the central point for dental movement of which is set with respect to a multi-rooted tooth to be positioned at a distance of between 1 and 2 mm downward from the furcation from which the root of the tooth bifurcates.