With the rapid development of industrial and agricultural production, a large number of industrial waste ' s metallic ions have entered into the groundwater system through various channels, which brings a great threat to the use of the groundwater resources. On the basis of the project of 300 000 tons PVC combined with a necessary item of 250 000 tons ion-exchange membrane caustic soda of the Pingdingshan Coal Group, Henan province, China, an experimental research on the static adsorption of clay minerals for metal ions in wastewaters was carried out. The results showed that clay minerals have a high affinity for the Na+, Hg2+  adsorption, in which pH value is an important factor affecting the adsorption effect. The higher the pH value, the larger the cation exchange capacity becomes. The results lay the foundations of fully utilizing sewage and purification ability of clay minerals in arid and semi-arid areas, and also provide a basis for searching environmental protection materials in sustainable development.