This paper conducts a correlation analysis between the borehole strain and water-tube tilt deformation at Yongsheng Seismic Station and the daily cumulative rainfall over a selected period, and constructs corresponding regression models. The results show that the responses of different observational components to rainfall vary. Among them, the east-west component of borehole strain and the north-south component of water-tube tilt exhibit stronger correlations with rainfall. On this basis, by marking the 1-standard-deviation line in the regression models of these two components, measured values exceeding this threshold are identified as outliers, whose occurrence shows no obvious correlation with rainfall events. The relationships between these outliers and subsequent earthquakes with M≥5.0 in Yunnan Province within one year are then analyzed. The study finds a certain degree of correlation between anomalies in the two components and later earthquakes with M≥5.0. In terms of spatial distribution, the earthquake events are mainly concentrated along the central and southern boundaries and within the interior of the Sichuan-Yunnan block.