**Abstract**

Due to the direct achieving for the state of stress or the strain along the earthquake fault which is quite essential in the assessment for the potential of strong earthquakes, the method of nowcasting earthquakes using the 'natural time' concept has been used in several locations worldwide and shown significant result. In this work, the Earthquake Potential Score (EPS) was determined using the nowcasting approach before several earthquake cases in the China Seismic Experimental Site (CSES) and analyze the consistency with the observation to evaluate its effectiveness. Firstly, with the importance of the data quality to this statistical method, we describe the background seismicity of the CSES area. Secondly, ergodicity research demonstrates the differences that exist in sub-regions such as Sichuan and the Yunnan region, mainly due to the simultaneous impact with the 2008 Wenchuan 8.0 earthquake. In the end, the strong earthquake potential prior to four earthquakes with magnitude larger than 6.0 was ultimately determined using the nowcasting method, which has EPS above 0.8. This may give support for the interpretation of EPS in earthquake nowcasting and will serve as a key reference for the ongoing development of this technology.

**Keywords:** China seismic experimental site (CSES), "natural time", nowcasting method, earthquake potential, strong earthquakes
