The invention provides a power network traffic anomaly detection method and device. The power network traffic anomaly detection method comprises the steps of collecting a data traffic packet of a power network, wherein the data traffic packet is composed of data of multiple fields; and establishing a k-d tree based on the data traffic packet, and carrying out anomaly detection on the data traffic packet. According to the method and the device, specific classification does not need to be carried out on power network traffic when detection is carried out; the detection difficulty is reduced; the method and device can be well adapted to various newly occurring anomalies; and after improvement is carried out through utilization of the k-d tree, the detection time complexity is reduced, and the time cost is clearly reduced.