Yttrium tantalate-based phosphors are a class of efficient luminescent materials used in medical imaging applications. The paper presents the influence of activator concentration, firing regime and flux nature on the crystalline structure, morphology and luminescent characteristics of niobium activated yttrium tantalate powders. Phosphors samples were prepared by solid-state reaction route and their properties were investigated by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), photoluminescence (PL) measurements and scanning electron microscopy (SEM).