Porous Indium phosphide has many potential applications in optoelectronics and chemical sensors. We report on the personification of Indium phosphide via a cost-effective, metal-assisted photochemical electroless etching technique with silver as the catalyst. The etching process was conducted at room temperature with optimized parameters. The synthesis mechanism for the porosification using the metal-assisted photochemical electroless etching method is presented. The morphological, structural, and optical features of the developed porous InP were studied with an appropriate characterization technique, and the obtained results were presented. The scanning electron micrograph exhibited the porosity nature along with the porous network of the etched sample. Photoluminescence (PL) measurements of porous InP shows a red-shift PL peak compared to the as-grown sample associated with the relaxation of compressive strain. Porous InP has a high specific surface and will present potential gas sensors applications and can be used as a substrate to grow semiconductor material with lower mechanical strain.