Salts of kukoamine B, their preparation method and their pharmaceutical use in preparation of drugs for preventing and treating sepsis. Experiments indicate that salts of kukoamine B have a good effect on antagonizing the key factors inducing sepsis, and can be used in the preparation of drugs for preventing and treating sepsis. Under the current circumstances of the lack of effective measures for the treatment of sepsis in clinical practice, the medicinal formulations, which comprise the salts of kukoamine B, pharmaceutically acceptable carrier and/or diluent, provide a new approach for the prevention and treatment of sepsis.