The invention discloses a preparation method for anhydrous praseodymium chloride. The method comprises the following steps: step 1, performing first-stage fluidization dehydration on praseodymium chloride heptahydrate under the temperature of 60 DEG C-100 DEG C to obtain a crude product of praseodymium chloride trihydrate; step 2, performing second-stage fluidization dehydration on the crude product of the praseodymium chloride trihydrate under the temperature of 120 DEG C-130 DEG C to obtain a crude product of praseodymium chloride monohydrate; and step 3, performing third-stage fluidizationdehydration on the crude product of the praseodymium chloride monohydrate under the temperature of 140 DEG C-160 DEG C to obtain the anhydrous praseodymium chloride, wherein the third-stage fluidization dehydration is carried out in a hydrogen chloride gas atmosphere. According to the preparation method for the anhydrous praseodymium chloride provided by the invention, the praseodymium chloride heptahydrate is subjected to staged fluidization dehydration, and the hydrogen chloride protection gas atmosphere is provided, so that hydrolysis in the process of dehydration of the intermediate product praseodymium chloride monohydrate to the anhydrous praseodymium chloride is effectively inhibited, and the product purity is greatly improved; and the preparation method for the anhydrous praseodymium chloride has the advantages of a low dehydration temperature, low preparation costs and good dehydration effects.