Abstract: In this paper, the soil conditions of two sites at Tianjing area during Tangshan earthquake are compared and analyzed, to find out the influence of soil behavior on liquefaction and finally to present the method of evaluating liquefaction potential of low plasticity clays. This method will make correction for the numbr of blows of standard penetration test according to clayey content. This corrected value is called equivalent number of blows,in which α = coefficient of correction, its values are taken from the following table,clayey content（%）≤3456789101112coefficient of correc-12.052.302.532.752.943.133.363.483.67tion aThe results of this correction method with equivalent number of blows are satisfactory. Ln addition, the possibility for evaluating the liquefaction potential of low plasticity claps by static cone penetrometer is investigated. It is considered that the results of static cone penetrometer are corrected to equivalent number of blows according to the recommendation in this paper. And then the method of evaluating liquefaction potential is used as before.