Barium strontium titanate (BST) Ba 1− x Sr x TiO 3 nanopowders have been successfully synthesized using the sol-gel route. This systematic study examines the effects of increasing strontium ions on the structural, morphological, and optical properties of the BaSrTiO 3 compound. The x-ray diffraction (XRD) results revealed that the polycrystalline barium strontium titanate (BST) phase was formed at greater than 700°C. The samples crystallize in pure perovskite and change from tetragonal to pseudo-cubic or cubic when Sr +2 ions increase. In addition, the effect of Sr +2 ion replacement on the crystal structure and optical characteristics of Ba 1− x Sr x TiO 3 particles (with x ranging from 0.2 to 0.6) was studied. The rise in Sr +2 from x  = (0.2 to 0.6) reduced particle sizes from 91.39, nm 288.89 nm, 144.88 nm, 86.42 nm, and 46 nm revealed by field emission scanning electron microscopy. With the increase in Sr +2 ions, the density, lattice parameter, particle size and cell volume are reduced. The percentage of porosity increased as the concentration of Sr +2 ions increased. Spectrophotometer readings indicated that the optical gap energy changed with Sr +2 ion concentration x. The optical gap energy changed toward low energy and fell from 3.6 eV to 3.2 eV when the ion concentration of Sr +2 rose from 0.2 to 0.6.