The invention provides a cascade target recognition method and system based on deep learning, and the method comprises the steps: obtaining a to-be-detected sample of an inspection image, marking a target detection sample, and expanding the number of samples; fusing multiple features of the image enhancement data to carry out a multi-stage deep learning detection algorithm, realizing significant equipment detection for a target with a large proportion, and eliminating noise interference of a complex background on the detection algorithm. Multi-stage deep learning algorithm detection is carriedout by fusing multiple features of image enhancement data, so that the detection accuracy of deep learning in small target detection is improved, and the influence of image quality on the detection algorithm is reduced.