This invention relates to a crystallization apparatus for preparing lithiumhexafluorophosphate, comprising: a tank body, a feeding device provided on the top surface of the tank body, and an array of heat exchange components provided on the inner wall of the tank body. The heat exchange components include several heat exchange plates disposed on the inner wall of the tank body and arranged along the length of the tank body. This apparatus can increase the heat exchange area and enhance the heat exchange efficiency, enabling the uniform and rapid precipitation of lithiumhexafluorophosphate crystals, and achieving continuous production with simultaneous crystallization and scale prevention.