Highly crystalline bare and N-doped SrTiO₃ nanoparticles were effectively synthesized with strontium acetate, titanium isopropoxide, hexamethylenetetramine as precursor via citric acid assisted hydrothermal process followed by calcination. The hydrothermally synthesized bare and N-doped SrTiO₃ NPs possessed monodispersity throughout with particle size diameter 50±5 nm but because of annealing at 750 °C temperature the synthesized NPs got agglomerate which created rough surface and induces oxygen vacancy in the NPs. Introducing N3- ions impurity into SrTiO₃ lattice tailored the electronic band structure of SrTiO₃ and extends its absorption into the visible region. It would display the p-type conductivity and facilitate the photoinduced electron-hole pairs towards respective site which diminishes the chances of recombination of electron-hole pairs that enhances photocatalytic degradation reaction. The results showed MB degraded about ~88 in just 140 min and followed first order reaction kinetics with rate constant k = 0.01489 mint-1.