Abstract: The present invention relates to a Salmonella bacteriophage, in particular to a Siphoviridae bacteriophage with a wide host spectrum and a strong lytic activity against Salmonella pullorum. The above-mentioned Salmonella pullorum bacteriophage is named SP4, and is deposited at the China General Microbiological Culture Collection Center, the deposit date is Jul. 27, 2017 and the deposit number is CGMCC No, 14332, The bacteriophage has a strong lysis effect on Salmonella, and the bacteriophage can also reduce the mortality rate of chicks infected with Salmonella pullorum, The preparation can be used alone or as a cocktail, and provides a safe, non-toxic and side-effect-free and residual effect-free bacteriophage product for the treatment of the infections caused by Salmonella of chicken origin, Salmonella of duck origin, Salmonella of mink origin, Salmonella of food origin and Salmonella of pig origin.