Annual relaxation of the seismic energy between 1900 and 2010 in West Chinese Mainland and Its Adjacent Areas has been deal with wavelet method. The active period of 46, 24, 15 and 7 year in seismic activity have been found by this method. This result, that there are 4 main period in seismic activity, is statically although the results have small difference when the data of the different time term have been used. It would be suggested that the boundary effect of the results should be considered when we make the earthquake prediction for the future seismic tendency. At same time the relation between the five years frequency for M≧5 from 1970 in western China and LOD also found. Two years after the turning of LOD is high occurrence for M≧5.