介绍了由渗透方程，经理论推导得到一个滤膜渗透速率常数与氡子体２１８Ｐｏ 衰变放出的α粒子脉冲计数的简单公式，设计了测量滤膜渗透速率常数的实验方法。测量结果表明，该方法的测量一致性好 A simple formula for counting the permeation rate constants of filter membrane and α particles pulsed by 218Po decay of radon progeny is deduced from the permeation equation and theoretical deduction. The experimental method for measuring the permeation rate constant of filter membrane is designed. The measurement results show that the method has good measurement consistency