The invention discloses an imaging spectrometer calibration device, which comprises a calibration device supporting seat, a diffuse reflection calibration plate, a diffuse reflection calibration plate driving mechanism, a reflector and a reflector driving mechanism. The diffuse reflection calibration plate driving mechanism drives the diffuse reflection calibration plate to rotate; when the diffuse reflection calibration plate rotates to the horizontal direction, sunlight is transmitted onto the diffuse reflection calibration plate and is reflected to enter an imaging spectrometer main optical system through the reflector so as to realize the light spectrum and radiation calibration function; and when the diffuse reflection calibration plate rotates to the downwards vertical direction, a ground object enters an imaging spectrometer through the reflector so as to enter an imaging state, and the reflector driving mechanism can drive the reflector to rotate so as to realize different imaging viewing angles. When the diffuse reflection calibration plate, the reflector and the calibration device supporting seat are closed, the imaging spectrometer is positioned in a dustproof and heat-insulating state. The invention has the characteristics that: the calibration device is compact in structure and has calibrating, imaging, dustproof and heat-insulating functions.