To provide a data processing device of production equipment that can generate data usable by an operator or an administrator by performing processing for a collected plurality of types of data. A data processing device includes a reference-data acquiring unit configured to acquire, in production equipment, reference data including information concerning time in which a reference for grouping of data operates, a target-data acquiring unit configured to acquire target data concerning a state of the production equipment detected by detectors provided in the production equipment, and a combined-data generating unit configured to generate, for each group of the reference data, combined data for each group obtained by combining, with the reference data, data detected in the same period of time as an operation period of time of the reference data in the target data.