该文提出了三种消除数字地震信号中长周期随机干扰的方法:①多项式拟合模板法;②窄带低通滤波对消法:③自适应高通滤波法.用多级抽点技术可使滤波法的运算量大大减少,并可获得良好的滤波特性.最后对三种方法进行了讨论并给出了实验结果.“,”This paper proposes the methods with which the long distubance is removed in the digital seismic signal: polynomial approach pattern methods, narrow band lowpass filtering cancelling method and adaptive highpass filtering method. The amount of calaulations of th filtering mehtod may be reduced greatly with many grades dacimating dacimating and the excellntly filter property may be obtained. Finally, the descussion to the three methods is presented.