The transmission line connection point is a major weak point of inline operation. In the operation of often heat burned, thus causing power outages. The analysis of the wire connection point heating problem, and timely adoption of appropriate preventive measures, will effectively avoid the wire connection point overheating. This causes the wire connection point to burn off the accident. Analyze the causes of wire connection point heating, and understand the theoretical basis for the temperature rise of high-voltage lines. At the same time, mastering the prevention and solution measures to deal with the connection point heating problem, to ensure the safe and reliable operation of the line has practical significance.