Synthetic Aperture Radar (SAR), as an all-weather, all-weather high-resolution imaging radar, can improve its maneuverability and reduce costs by carrying UAV platforms, making it widely used in military and civilian fields. The working mode of the traditional airborne SAR system is that the UAV obtains the original echo data and processes it on the ground. This processing mode has obvious drawbacks, which greatly reduces the timeliness of its acquisition of ground information. In this paper, a real-time imaging method of airborne SAR based on embedded GPU is proposed. Through the embedded GPU (NVIDIA Jetson TX2) mounted on the UAV, the raw echo data obtained by the UAV is processed in real time. Parallel computing capability for real-time imaging processing. The real-time processing results are downloaded to the ground receiving station through the wireless data transmission module, which greatly improves the real-time performance and practicability of the system.