Based on the crystal chemistry characteristics of industrial vermiculite, the application mineralogy characteristics of the industrial vermiculite samples from four Mines in China have been studied. The results show that the samples are composed of phlogopite-vermiculite and chlorite-vermiculite interstratified minerals. The interstratified structure characteristics and the vermiculite layer contents are different in the different samples even for the samples from same Mine. The chemical compositions have difference in the different interstratified structure type samples. The contents of K2O, TiO2 and Na2O are higher for the samples with phlogopite-vermiculite interstratified structure and the contents of MgO and Al2O3 are higher for the samples with Chlorite-vermiculite interstratified structure. The cation exchange capacities of the samples are between 17.26mmol/100g and 98.95mmol/100g. The thermal expanding ratios of the samples are between 9 and 32. The samples with more vermiculite layers have bigger cation exchange capacity and the thermal expanding ratios.