Abstract: This paper analyzes the time-frequency characteristics of groundwater level, temperature and geochemistry, according to the monitoring data from Wuliying monitoring Well, Yanqing, Beijing. The results show that: ①These monitoring data have convex and cluster peak in time domain, and also have significant abnormalities such as enhancement of high frequency short period in the frequency domain. ②These monitoring data have obvious time distribution pattern: the groundwater level, temperature, gas and anion respectively showed abnormal changes from 2014 to 2016. ③The abnormal time-frequency characteristics of monitoring data of Wuliying well may likely indicate the intensification of seismic activity in 2016 in the study area and adjacent areas.