Abstract: The gliding arc discharge has wide application potential in the field of energy, environmental and material treatment. In order to provide guidance to the optimization of the electrode configuration and the operation parameters as well as the enhancement of the performance in the practical application, the discharge mode, the voltage-current characteristics, the emission spectrum and the arc motion characteristics of the gliding arc discharge driven by the high- frequency alternating-current power supply are systematically analyzed based on the voltage and current signals and the discharge images obtained by the approaches of electrical and optical analysis. The influences of gas flow rate and the input voltage of the regulator have been discussed. The results show that two gliding modes are observed in the whole discharge process, including the steady arc gliding (A-G) mode and the breakdown gliding (B-G) mode. There are significant differences in the electrical signal characteristics and arc motion characteristics between the two modes. Lower gas flow rate and higher input voltage are beneficial to achieve the A-G mode. The average discharge power and gliding period in the A-G mode are higher than those in the B-G mode. The large arc height and length are also obtained in the A-G mode. In addition, the emission spectrum intensity is also related to its discharge mode. The spectral intensity of the reactive species that generated in the A-G mode is higher than that in the B-G mode, which is beneficial to initiate chemical reactions. Therefore, in the practical application of gliding arc discharge, the plasma with high stability and activity for the enhancement in the application performance can be achieved by operating the discharge with relatively lower gas flow rate and higher input voltage (e.g. 3L·min^-1 and 120V in this work).