Abstract: Based on the past 10 years vertical observational waveforms recorded by Lanzhou small aperture seismic array, which is located at the northeastern margin of the Tibetan Plateau, the observed travel-time curves are obtained by using STA/LTA technique. The results show that Lanzhou seismic array can record events with different epicentral distances between 0—180° and with different azimuths due to its particular location. By stacking the seismic records filtered with different frequencies, we can get corresponding observed travel-time curves so as to identify different body wave phases, such as P, PKIKP, PKP, PP, PPP, PcP, ScP, S, SS, and to study the characteristics of travel-time curves. It is of scientific significance to identify various seismic phases and further study fine structure of the Earth’s interior.