The invention provides a preparation method of a powdery bdellovibrio bacteriovorus lyophilized preparation with high survival rate. The method comprises the steps of obtaining a bacteria solution or a bdellovibrio bacteriovorus bacterial suspension from which a harmful host is separated according to a conventional culture method of bdellovibrio bacteriovorus; preparing a protective agent solution; carrying out freeze drying on a to-be-lyophilized mixed solution, repeatedly vacuumizing and filling an inert gas to finally prepare the preparation into powder; and carrying out sealing packaging on the bdellovibrio bacteriovorus lyophilized preparation under a vacuum condition or under the condition of filling the inert gas to prepare a finished product, namely the bdellovibrio bacteriovorus lyophilized preparation. Through compounding of multiple lyophilized protective agents, the freeze-drying survival rate of bdellovibrio bacteriovorus is improved, the character of the bdellovibrio bacteriovorus lyophilized preparation is powder, and dispersion and compounding of the lyophilized preparation are facilitated.