Object detection is the foundation of computer vision applications. Some object detection algorithms based on anchor boxes have been unable to meet the requirements for object processing efficiency and performance in object detection, and anchor free method is gradually widely used in object detection. This article firstly introduced a series of key-based anchor free object detection methods based on the CornerNet, CenterNet, and FCOS model, and summarized the algorithm ideas, their advantages and disadvantages. Then the performance comparison and analysis of the object detection algorithm based on anchor boxes and key points were performed on the same data set. Finally, the object detection based on key points was summarized, and the future development direction of object detection was prospected.