The invention discloses a method for obtaining spectrum-integrated time-varying target optical spectrum information and a device thereof. The method specifically comprises the steps of: obtaining a current frame image of a scene; extracting candidate interest regions which comprises time-varying targets therein; respectively leading the each candidate interest region to be associated with each interest region obtained from the last frame; confirming the candidate interest regions which are successfully associated to be interest regions; assigning the identification of the interest regions to the identification of the last frame interest region which is successfully associated therewith; and obtaining optical spectrum data of the each interest region of the current image. The invention also designs a device for realizing the method, which comprises a main control unit, an imaging sensor, an optical spectrum sensor, an infrared spectroscopy lens, a tracking reflecting mirror and a tracking and scanning rotary table. The invention provides a data acquisition method for combining a wide imaging optical spectrum with a wide non-imaging optical spectrum; and compared with a normal method for acquiring optical spectrum data of the all regions of the whole scene, has fast reaction speed and low cost, is suitable for the intellectualized acquisition of the time-varying target optical spectrum data, and improves the cost-effectiveness ratio for acquiring the optical spectrum date.