张北6．2级地震发生之前，区域地震活动显示出了明显的异常特征。作者在近几年来对北京西北—晋、冀、蒙交界地区的震情趋势变化给予了高度的注意，根据近几年来华北地区地震活动的总体变化，提出了华北北部地区存在发生强震的危险；尤其是在1997年10～11月，提出了华北地区1998年3月下旬（误差为±5个月）可能会发生Ms6～7级地震的中期预测；并且在强调华北地区存在多源孕震的特征以后，认为“北京西北—晋、冀、蒙交界地区地震活动某些前兆异常出现的时间较早，异常时间较长，故应注意该地区首先发生强震的可能性。” Prior to the Zhangbei M6.2 earthquake, regional seismicity showed obvious anomalous characteristics. In recent years, the author has paid close attention to the trending changes in the areas northwest of Beijing, the junction of Shanxi, Hebei and Mongolia. According to the general changes in seismic activity in North China in recent years, the authors put forward the danger of strong earthquakes in the northern part of North China Especially in the period from October to November 1997, proposed the medium-term prediction that Ms6 ~ Ms7 earthquakes would occur in northern China in late March 1998 (with an error of ± 5 months); and stressing the existence of multi-source seismogenic After that, it is considered that “some precursory anomalies in the seismic activity in the northwestern Beijing-Jin, Ji and Mongolian border regions occur earlier and have a longer anomaly, so attention should be paid to the possibility of strong earthquakes first occurring in the area.”