Abstract: To reduce acid corrosion of equipments, improve extraction of zanthoxylum nitidum alkaloid technology. The method of acid decompressing inner ebullition was used to intensify the extraction of nitidine chloride, comparing acid decompressing inner ebullition with other seven methods by HPLC fingerprint. Experiment results showed that the yield of nitidine chloride reached 0.132% , the purity of crude extract reached 0.657%, when the powder of zanthoxylum nitidum was firstly immersed into 3mL·g -1 solvent, which was composed of 80wt% ethanol and 0.61wt% HCl and then was extracted by 16mL·g -1 solvent, which was composed of 40wt% ethanol, at 50℃ for 3min, the pressure was 0.020MPa. Comparing with different extraction technology of HPLC fingerprint, acid decompressing inner ebullition was the same as other methods in the number of peak and type of peak, but its nitidine chloride peak area and the percentage of nitidine chloride peak area were both big, extracting safely and efficiently, which obviously reduced acid corrosion of equipments during extraction process.