Abstract: Bentonite in China is rich in resources, but its exploitation development and utilization is severely limited restricted by to the mineral occurrence attribute and grade level. ore properties and grade level. In order to strengthen the development and utilization of bentonite, the purification, sodium and organic modification of the low low-grade Ca-bentonite are were introduced in this paper. It involves, including the principle of preparation, the process technology, the advantages and disadvantages, the influencingcontrol factors on process and the characterization methods during the course of preparation.