The Micro-Crystalline Cellulose （MCC）was prepared by acid hydrolysis method from Artemisia. The effects of solid to liquid, concentration of hydrochloric acid, temperature of acid hydrolysis and time of acid hydrolysis on the yield and degree of polymerization of Artemisia MCC were studied by single factor experiment. The preparation process of MCC was optimized by response surface methodology, and the structure and properties of the microcrystalline cellulose were analyzed. The optimum preparation conditions of MCC were as followed: ratio of solid to liquid 1∶30 （g/mL）, concentration of hydrochloric acid 15%, temperature of acid hydrolysis 70 ℃, and time of acid hydrolysis 60 min. Under the optimum conditions, the yield of MCC is 85.14%, the degree of polymeriz-ation is 182.7, the crystallinity is 72.85, the swelling power is 12.5 mL/g, and the hydraulic capacity is 13.875 g/g. The obtained Artemisia MCC has good properties, and is an ideal dietary fiber.