Abstract: 【Objective】To separate and identify the flagellin from Salmonella anatum.【Method】Salmonella anatum was induced with semisolid medium for flagellin, and cultured with M broth, then obtained by centrifuging. The flagellin was separated by acid-splitting and differential centrifugation, ammonium sulate precipitationi. The obtained flagellin was evaluated by sodiummdodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), phosphotungstic acid negative staining and electron microscopy. Antigencity of flagellin was detected by direct ELISA. 【Results】SDS-PAGE showed that the purified flagellin protein molecular weight was 58KD; the protein possessed good antigencity and 1000 milliliters of culture produced 32.8mg flagellin.【Conclusion】The flagellin with good antigencity from Salmonella anatum can be obtained by acid-splitting. The purified flagellin may lay the foundation for developping methods for avian paratyphoid diagnosis.