A compressed sensing based object imaging system and an imaging method thereof. The object imaging system comprises a light source generation unit (11), a filter unit (12), an image generation unit (13), an image acquisition unit (14), and an image reconstruction unit (15). The light source generation unit (11) generates experimental laser; the filter unit (12) filters high frequency scattered light and forms parallel light; the image generation unit (13) generates an experimental image in which an object image (16) and a specific measurement matrix (17) are superimposed; the image acquisition unit (14) performs compression sampling on the generated experimental image; and the image reconstruction unit (15) reconstructs sampling data to restore the object image (16). The imaging method comprises: establishing a sample database comprising the specific target object image (16); training sample images to obtain the specific measurement matrix (17); and simultaneously completing image sampling, image compression and image recognition in an all-optical system. The system and the method can greatly reduce the data volume recorded in image recognition and image matching, thus improving the real-time performance of the system, and providing a possibility of concurrent processing by machine vision and artificial intelligence.