As an important research direction of computer vision

visual object detection has been widely used in face detection

pedestrian detection

unmanned driving and other fields. With the breakthrough of big data

computer hardware technology and deep learning in image classification

target detection algorithm based on deep learning has become the mainstream. Research status and development of target detection algorithm based on deep learning is reviewed. Research progress and classical model for convolutional neural network（ CNN） is introduced.Development

improvement and shortcomings of the current mainstream two-stage target detection algorithm and single-stage target detection algorithm based on deep learning is summarized. Compare the two main current algorithms of deep learning target detection and make a summary and future outlook.