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Cellulose acetate is a material widely used in industrial fields. Cellulose triacetate (CTA) was synthesized by a one-pot method using corn stover cellulose as raw material and trifluoroacetic acid (TFA) as catalyst. The effects of TFA content, reacting temperature, reacting time and acetic anhydride content on the degree of substitution and yield of CTA were studied. At the same time, the synthesis process of cellulose triacetate was optimized. The results showed that the optimal optimization conditions for CTA were as follows: the content of TFA was 15mL/g, the reacting temperature was 25℃, the reaction time was 30min, and the content of acetic anhydride was 5mL/g. Under these conditions, the degree of substitution and yield of CTA were 2.95 and 96.2%, respectively. Fourier transform infrared spectroscopy, X-ray diffraction analysis and hydrogen nuclear magnetic resonance analysis were used to characterize the physical and chemical properties of the product. The results showed that acetylation of cellulose occurred and CTA was synthesized. The thermogravimetric analysis results showed that the CTA prepared by this process had better thermal stability and the purity of the product was higher. A process for the efficient preparation of corn stover cellulose CTA with one-pot method was constructed, which provided a way for the high-value utilization of corn stover. At the same time, the method can recover the catalyst TFA without adding additional solvents, reducing costs while reducing resource consumption. It can provide certain theoretical basis and technical support for the efficient utilization of corn stalks and the industrial production of cellulose acetate in the future.