Abstract: This paper, by theory and calculatnig method in References 1~4 analyzes the characteristics of the continuous observation results at four earth stress stations of Xingtai and others in the period of 1982-1988. It is found that, compared with the results of 1974-1984, the recent results show various variations with precursorycharaeteristics, such as the systematic variation, accidental variation, dynamic proportional factor variation, ratio variation and weighted corresponding coefficient of the dynamie base line of additional stress parameters. These variations may be the information of stress anomaly associated wfth earthquake preparation an occurrence in North china area.