An abnormality determination system includes first data acquisition circuitry configured to acquire time-series data relating to an operation of a device, sample data creation circuitry configured to create sample data based on abnormality time-series data which the first data acquisition circuitry acquires while an abnormality occurs in the operation of the device, and first abnormality determination circuitry configured to determine the abnormality in the operation of the device based on the time-series data and the sample data.