The water solubility of methyl- beta-cyclodextrin is very high at room temperature, which is generally greater than 75%. It is widely used in animal health products (pet medicine) and cosmetics. methyl -beta-cyclodextrin is more powerful than other cyclodextrins. In particular, its inclusion ability of oil soluble molecules is strong. The methyl- beta-cyclodextrin is produced by Zhiyuan Biotechnology is divided into two types: high degree of substitution methylated-beta -cyclodextrin and low degree of substitution methylation of β -cyclodextrin .The average degree substitution of RM- β -cyclodextrin (RM- β -CDL) is MS=4-6. Both of them have good water solubility and increase with the increase of temperature. The highly substituted methyl-beta-cyclodextrin is more water-soluble than the low-substituted methyl-beta-cyclodextrin and soluble in ethanol and chloroform. The solubility is greater than 100 g / 100 ml at room temperature. Low-substituted beta-cyclodextrin is soluble only in water and ethanol, but not in chloroform. The solubility of the water at room temperature is about 50 g / 100 ml. The envelop ability of them to the guest substance is larger than that of the parent beta-cyclodextrin. The viscosity reduction effect of the thickener is higher than that of the low-substituted methyl-beta-cyclodextrin, and the high-substituted methyl-beta-cyclodextrin is superior to the low-substituted methyl-beta-cyclodextrin. Methyl beta-cyclodextrin has good solubility and is an ideal solvent and stabilizer for guest substances.