Taking the advantage and basic condition of comprehensive test centre built on real overhead transmission line (which belongs to State Grid Company of China), the conductor tension during galloping for 500 kV 6-bundle transmission line was measured and analyzed by using artificial airfoils with D shape on conductor, which had been proved to be quite essential for galloping excitation. Through the frequency spectrum comparison and the correlation analysis with wind load, the characteristics of conductor dynamic tension during galloping were obtained. It was shown that the conductor dynamic tension could be used as one of the critical parameters for galloping, which would not only be used for reliable analysis of tower-line system, but also be applied for the monitoring and identification of transmission line galloping. In a word, the characteristics of conductor dynamic tension during galloping are the basic data for the pre-warning of galloping and the performance evaluation of anti-galloping measuring.