This study shows that Keyhole Gas Tungsten Arc Welding (KGTAW) process enabling a single pass of 10 mm thick AA6063 alloy can be used without expensive filler metal addition or joint preparation. KGTAW has significantly high productivity as well as simplicity of proven technology and low capital investment requirements. It can be successfully applied in the welding of AA6063, without sacrificing the metallurgical quality associated with the Gas Tungsten Arc Welding (GTAW) process. After. KGTAW, to determine the microstructural changes and to observe phases and compounds generated on the interface, welded samples were examined by OM, SEM and XRD. In addition, microhardness, tensile and notch impact strength tests were applied to determine the mechanical properties of welded samples (Si, 550 A and S2, 600 A). The best result was obtained for the S2 sample in the KGTAW technique.