Abstract: Pathogeny of northeast tiger was separated and identified in Jilin City Jiangnan Park. In order to carry out the epidemiological investigation and provide the accuracy diagnose and treatment measures, toxA gene of pastuerella was researched in the experiment. According to pastuerella toxA gene rank, a pair of primer was designed and synthesized. The rank of toxA was amplified by pastuerella toxA in clinical. 526 bp aim gene were cloned into pGEM-T vecter and the cloning vecter pGEM-TtoxA was constructed. The sequences of toxA gene have 100% homology with that of the standard toxA in (X51512). Epidemiological investigation showed that etiological agent of northeast tiger pastuerella Multocida maybe comes from the food. So it is important to quarantine in feeding and cut off the route of transmission in breeding.