An inspection device includes: an irradiator that irradiates an object with near-infrared light; a spectroscope that disperses reflected light from the irradiated object; an imaging device that takes a spectroscopic image of the reflected light; a processor that: obtains spectral data of a plurality of points on the object, based on the spectroscopic image; defines a group of similar spectral data from among the spectral data of the plurality of points; extracts a group having a largest number of spectral data from the defined group; calculates an average of the spectral data of the extracted group; and detects a type of the object using a predetermined analysis of the object, based on the average.