An object of the present invention is to provide a monitoring device which facilitates determination of prediction of trouble while preventing excessive reporting. A monitoring device (20) includes: a physical quantity acquisition section (201) for acquiring physical quantities indicative of a state of a device; an abnormality determination section (203) for determining, in accordance with whether or not the acquired physical quantities fall within a predetermined range, whether or not there is an abnormality; an abnormal waveform data generation section (204) for, in a case where the abnormality determination section (203) determines that there is an abnormality, generating abnormal waveform data indicative of a change over time in the physical quantities acquired during an abnormal waveform period containing at least a period from a point in time at which the abnormality determination section (203) determines that there is an abnormality to a point in time at which a predetermined accumulation time elapsed; and a reporting section (206) for causing a display section (207) to display an abnormal waveform indicated by the abnormal waveform data.