Bi2O2Se, a layered oxychalcogenide has gained much attention among the conventional oxides and chalcogenides based thermoelectric materials because of its high stability and less toxicity. Herein, Bi2-xPrxO2Se (0 ≤ x ≤ 0.15) is synthesized by ball milling followed by hot press densification technique, the x represents the replacement of Bi with Pr in atomic%. The influence of isovalent Pr substitution on the structural and thermal transport properties of Bi2O2Se were studied. The formation of tetragonal crystal structure with space group I4/mmm is confirmed by X ray diffraction (XRD) Pattern. HRTEM micrographs reveals the crystalline nature and lattice defects in the synthesized composition. The influence of 10 at % Pr substitution at Bi site reduces the thermal conductivity to 0.276 Wm−1K−1 at 653 K, originated from short phonon lifetime due to the effect of mass and strain field fluctuation. This result exhibits that the incorporation of Pr substitution in Bi2O2Se can dramatically enhance the thermoelectric performance of Bi2O2Se ceramic by reducing thermal conductivity.