Metal matrix composites are an appealing alternative to monolithic metals for a variety of technical applications due to their superior mechanical and physical properties throughout a broad range of operating conditions. In the current study, different weight percentages of 150 µm groundnut shell ash (GNSA) particles (2.5%, 5%, 7.5%, 10%, 12.5%, 15%, 17.5%, 20%, 25% and 30%) were used to reinforce Al-Mg-Si alloy. Stir-casting was used to prepare the composite in a permanent mild steel mould. A number of the composites' physical, chemical, and microstructural characteristics (density, percentage porosity, XRF and SEM-EDS) were assessed, compared, and analysed with those of the matrix alloy. Oxides that could enhance the composites' mechanical, physical, and structural qualities were found during the structural assessment evaluation of the reinforcement. The microstructural analysis demonstrated that the GNSA reinforcements' secondary phase was uniformly distributed throughout the primary phase of the Al-Mg-Si alloy matrix. The added GNSA particles decreased the produced composite's density below that of the base alloy, and the percentage porosity of the composites rose as the groundnut shell ash content increased and remained within the upper limit allowed for cast aluminium metal matrix composites. The composites that were created showed evidence of intermetallic compound formation.