This article reports surface modification of Al-Si alloy LM13 (EN 1706 AC-48000) via plasma sprayed coating of Cr2O3. Small billets of cylindrical geometry are used as substrate material, having 10 mm diameter and 40 mm length as dimensions. Range of the thickness of coating varies between 200 and 250 µm with a stand-off distance of 4–5 in. and 50 kW, 600 amp as blasting factors. The microstructural examinations of the coated and uncoated samples are performed through Scanning Electron Microscopy (SEM) at high vacuum, 20 kV, and various levels of magnifications followed by EDX analysis of the elemental configuration of the specimens. Hardness tests are also carried out for determining physical strength. Improvement of surface hardness is studied for coated (Cr2O3 coating by plasma spray deposition) specimen compared to uncoated one. Cr2O3 coating specimen demonstrates satisfactory results in morphological investigation and hardness experiments where a 12–15% increment of the hardness values is observed. Plasma sprayed Cr2O3 ceramic coating samples can be employed in elevated temperatures as well as in an application where high hardness is needed such as cylinder and piston rings of IC engines.