Abstract: The magnitudes of 64 earthquakes in Hebei and its neighbouring region recorded by Hebei digital telemetered seismic network from Nov.of 2001 to May of 2004 were calculated with different method, and compared with the national monthly catalogue and the catalogue from national basic network.Through comparison we found the velocity magnitude determined from the maximum product method, which read the amplitude of S wave in 2 horizontal directions and its corresponding cycle by computer automatically, is relatively stable.For its small divagation and easy to calculate, it meets the need to determine magnitude effectively in quick report of strong earthquake.