The degradation of the arc extinguishing performance of high-voltage vacuum circuit breakers can easily lead to the generation of continuous arcs, damage to the contact surface and delay of the opening and closing time. In severe cases, a breakdown and explosion may occur. Therefore, research on monitoring the arc extinguishing performance of high voltage vacuum circuit breakers is important. Existing research methods for the arc extinguishing performance of high voltage vacuum circuit breakers consist mainly of measuring the vacuum degree of the arc extinguishing chamber, but there are problems such as long measurement period and inability to guarantee air tightness. The arc extinguishing principle in the arc extinguishing chamber is analyzed. Obtaining the arc extinguishing level in the chamber can be inverted using the influence of the arc resistance on the attenuation characteristics of the arc current when the medium is restored. Using this, the arc current trend item is extracted as the representative quantity of the arc extinguishing ability. An online detection method for the arc extinguishing ability of the high voltage vacuum circuit breaker based only on electrical quantities is proposed. This has the advantages of fast real-time monitoring and safety of measurement. The effectiveness of the method is verified by field measured data and digital simulation. This work is supported by the National Natural Science Foundation of China (No. 52077116).