The distribution and space-time change characteristics of the seismic apparent strain field in Songpan-Pingwu and the adjacent areas since 1970 to 1975 are studied, using the seismic data of this region. The result shows that there is a rather well corresponding relationship between the anomalous region of seismic apparent strain and the Songpan-Pingwu earthquakes in 1976. The anomalous region appeared in 1970 vents occurred just in the anomalous region.