Provided is an apparatus for generating dental data for manufacturing an aligner, the apparatus including: a dental-data generation unit, in which the dental-data generation unit includes a preprocessing module includes a first module that receives 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 generates 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 sets a central point for dental movement in the 3D data, a fourth module that sets 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 sets a reference for a dental root point in the 3D data.