Abstract By calculating RMS, PSD, and PDF value at 1 to 20 Hz band, the current study explores the suppressive effect on background noise, based on the comparison of underground, tunnel and surface seismological observed data from seismic stations Chifeng and Erenhot. The findings show that the underground observation has a significant suppressive effect of background noise in comparison with the tunnel and the surface over 2 Hz frequent bands, especially higher than 9 Hz frequent bands. The suppression of underground method would weaken when the frequency is less than 16 s. However, it disappears at 16 s to 2 Hz band. All three methods share a high level of coherence of background noise in the meantime. In conclusion, we can reduce background noise effectively through underground observation, so that the data quality will be optimized.