Method for preparing taltirelin tetrahydrate alpha crystal form crystal by using beater

The present invention provides a taltirelin (formula I) tetrahydrate alpha crystal form crystal preparation method, particularly to a method for preparing a taltirelin tetrahydrate alpha crystal form crystal by using a beater. The method specifically comprises: adding taltirelin to a non-protonic solvent, stirring, and using crystallization of the temperature difference method, solid-liquid separation, and drying to obtain the taltirelin alpha crystal form crystal. The method is characterized in that the stirring is specifically the complete stirring at a temperature of 20-60 DEG C by using a beater, the stirring speed is controlled to 300-500 r/min, and the non-protonic solvent is tetrahydrofuran, ethyl acetate, acetone, and acetonitrile. According to the present invention, the method has characteristics of good process stability, strong operability, high yield, and the like; and the obtained product has characteristics of low free water content, melting point close to the upper limit of the standard value, easy formulation processing, storage, and transportation, and the like. The formula I is defined in the instruction.