Abstract: Aimed at the problem of node selection and path planning in the process of edge computing task offloading, under the constraints of computing resources and network resources, an edge computing task offloading node selection algorithm (ETN) based on SDN is proposed. According to the request of task offloading, the SDN controller selected the candidate nodes that meet the task requirements, and carried out path planning for each candidate node. The candidate nodes were scored and sorted according to the computing resources and network resources to obtain the optimal offload node that could not only meet the computing resource requirements, but also have a preferable offload transmission path. After experimental simulation analysis, compared with the comparison algorithm, the proposed ETN algorithm has been effectively improved in the time of select offloading node, transmission delay, throughput and so on.