For the experimental study of liquefaction of saturated sands by shaking, there are generally two methods. One is by dynamic triaxial and dynamic simple shear tests, and the other is by means of a sand box on the shaking table. However, each has its merits and demerits. The major drawback with the latter method is that the stress conditions in the sand box cannot be regulated strictly. To cope with this problem, the author contrived a means of applying the consolidating pressure by use of compressed air, in order to reduce the disadvantage to some extent. In this experiment, it was confirmed that, for a given apparent density of the sand, the occurrence of its liquefaction is also determined by the ratio of shearing stress in the sand and initial effective pressure. Then, in order to evaluate the experimental results by a shaking sand box