以2004年内蒙古东乌珠穆沁旗M_S5.9地震为研究对象，对震中区域的地震活动参量b值进行时间扫描计算，M_S5.9地震前b值表现为高值回落；在选取的时空范围内，计算出震中区域平均波速比和地震空间相关长度，M_S5.9地震前波速比变化过程为下降—持续低值—回升发震，地震空间相关长度在震前趋势性上升，分析认为可以把波速比的和地震空间相关长度的震前变化规律作为同一区域未来地震的预测依据。

Take the Dongwuzhumuqinqi Ms 5.9 earthquake as the study object, sketchd the time sweep curves of b-value, then analyze their anomaly before the Ms5.9 earthquake; base on the selected space-time range, calculate velocity ratio(Vp／Vs) and correlation length of epicenter region, then discuss their variety trend before earthquake：the variety course of velocity ratio(Vp／Vs) is descend—keep low value—rally, the variety course of correlation length had ascending trend. So we Consider that the variety discipline of velocity ratio(Vp／Vs) and correlation length may be as the forecast basis before future earthquakes which occurred in the same area.