唐山地震前北京大灰厂、牛口峪台站的形变异常是至今被认为较为可靠的异常。本文着重剖析了两台站短水准与连通管资料。讨论了温度与降雨干扰的特点与机制;通过各项资料的对比、人工降雨干扰试验,论述了异常的可靠性;采用褶积滤波的方法基本上排除了观测数据中的温度与降雨干扰;分析了异常的特点,说明了地震前后八宝山断裂带的活动特点。根据唐山地震前后大范围形变场的演化及某些模拟试验结果,提出了唐山大震中期形变异常的模式,说明了异常与大震的密切关系。文中进一步分析了两台的主要特点,对形变前兆观测,特别是对监视断层活动,观测地震前兆的工作提出了值得重视和研究的某些问题。 Before the Tangshan earthquake, Beijing Dai Ash Plant, Niu Kouyu station deformation anomaly is considered to be more reliable anomalies. This article focuses on the analysis of the two stations short leveling and connectivity information. The characteristics and mechanism of temperature and rainfall disturbance were discussed. The comparison of various data and artificial rainfall disturbance test discussed the reliability of anomaly. Convolution filtering basically ruled out the temperature and rainfall interference in the observed data. The characteristics of the anomaly illustrate the characteristics of the Babaoshan fault zone before and after the earthquake. According to the evolution of large-scale deformation field before and after Tangshan earthquake and some simulation results, a model of mid-term deformation anomaly in Tangshan earthquake is proposed, which shows the close relationship between anomalies and large earthquakes. The paper further analyzes the main features of the two sets and puts forward some issues worthy of attention and research on the work of deformation precursory observation, especially for monitoring fault activity and observing earthquake precursors.