One of the most important causes of the destraction of dikes by waves is that the sand particles inside the dikes are drawn out by the waves. To analyze this kind of phenomenon theoretically, it becomes necessary to know the the flow velocity through the porous media. In the past, several studies have seen made on this problem. Here, an investigation is made on the possibility of measuring the flow velocity through porous media by the Allen method applying the variation of electrical conductivity by using salt water solutions. As the results, the accuracy of this method was found to be theoretically 98.4% and experimentally 97%, and it was found that the Allen method can be applied to measure the flow velocity through porous media.