At present, most of the image-based detection systems are mainly single-camera, but the field of view of a single image is limited, and there are often blind spots, so a panoramic object detection system based on four cameras is designed in this paper. Firstly, the system hardware composed of 3B+ Raspberry Pi, camera, LCD screen and mobile power supply was built, and a user interactive software interface for detection result display and parameter setting was designed based on QT. The system uses four cameras to frame the surrounding 360-degree scene, then preprocess and stitch the collected images, and finally perform object detection and result display through the EfficientDet-based deep learning model detector. Experimental results show that the system can be portable and mobile, and can realize 360-degree panoramic framing and target detection functions, and the accuracy of target detection is more than 94%.