In this paper,mica powder and acrylic monomer were selected as raw material and made it into a new water absorption polymer.To explore the basic water absorbing characteristic,its influences on the potassium supply of soil was studied by anindo or training experiment.Results showed that the absorbing char-acteristics of the cross-linked substance of mica powder and poly acrylic acid is desirable,especially the strong saline absorption.When applying it into soil in low dose,the cross-linked substance of mica powder and polyacrylic acid can improve the potassium supplying strength of soil and in high dose,it can raise the buffer capacity of soil potassium.