Abstract We study the data of Maduo MS7.4 earthquake in Qinghai province on May 22, 2021 recorded by second sampling YRY-4 borehole strain gauge and the resampling seconds of BBVS-120 seismometer observed at Gaotai station. We carry out comparative analysis of data variation characteristics, seismological phase morphology and spectral characteristics. We find that the coseismic record of borehole strain second sampling data is clear, and the coseismic record satisfies the self-check characteristics of the four-component borehole strain observation. Both sets of instruments can record the seismic phase of the earthquake, the seismic phase morphology is similar, and the seismic phase arrival time is basically the same. The frequency spectrum and time-frequency diagram of the two sets of instruments are similar, the spectrum components are close, but the frequency distribution and amplitude change are different. This is related to the observation principle, component(direction finding) orientation, frequency bandwidth and observation sensitivity of the instrument. To further analyze the dynamic significance of borehole strain, we conduct space projection of borehole strain at different time nodes, and combined with the relative orientation of the earthquake epicenter and the station, we find that the southwest northeast 2323 and 2324 components, which are approximately close to the epicenter pointing station, and the 2321 and 2322 components distributed perpendicular to the epicenter pointing station, are in opposite tension and compression states. This may be related to the propagation laws of P and S waves.