Using the digital waveform data recorded by six temporary digital seismic stations which was closed to the epicenters of the Yao’an M5.9 and M6.5 earthquakes in Jan., 15, 2000, applying the methods of the spectrum analysis and Brune’ theory, the authors obtained source spectrum parameters and source parameters of Yao’an earthquake sequence. The result shows that the seismic moments of Yao’an earthquake sequence are between 108N· m and 1014 N· m, the stress drops are between 0.005 MPa and 10 MPa, and the source radius is between 50 m and 660 m, and the authors obtain the relationship between seismic moment M0 and local magnitude ML. With the seismic moment increases the comer frequency reduces, but the stress drop increases. The source radius increases with the magnitude increases, but there is no evidence relationship between source radius and stress drops.