The contemporary work manifests that friction stir welding (FSW) is a viable avenue for joining AA1100 aluminium (Al) to C12200 copper (Cu) plates. In this present study, the response of distinctive welding parameters (viz. tool geometries, tool rotational speed, tool travel speed, and tool plunging depth) on weld quality has been investigated. The present work focused on both microstructural investigation and mechanical properties examination. It has been observed that the process parameters have significant effects on weld quality. The design of the experiments has been executed considering four welding input parameters in two variables and selected L-16 orthogonal array to limit the experimental replications. It has been observed that good quality of welds produced by keeping the tool pin offset around 4mm towards the aluminium side and 2mm towards the copper side. And it has also been noticed that right-hand threaded tool pins are giving good weld quality compared to left-handed thread. The joint efficiencies for the welds E2, E14 which were welded by RHT tools were 75.3% and 74.61% and the Strength (UTS) of the welds for the same tools exhibit’s greater than the LHT tools i.e., 98 and 95Mpa. Moderate hardness values are observed for the same welds E1 and E14 with the parameters 1100rpm, 98welding speed, and 1.6mm tool plunge depth. . It also noticed that the weld quality can be significantly enhanced by using proper tool plunge and tool pin geometries compared to the other process parameters.