A comparative investigation on the emission properties of CaWO4:Pr3+ microcrystalline powders and crystals has been carried out in order to understand the role of the lattice defects in the host to Pr3+ energy transfer process. The Pr3+ luminescence has also been measured as a function of the temperature in the 300–600 K range and the results have provided information on the processes involved in the excited states dynamics of the title material.