This document discusses a study on the effect of process parameters on tensile strength of friction stir welded AA6061 aluminum alloy joints. Friction stir welding is a solid-state joining process that uses a non-consumable rotating tool to join materials together without melting. The study examines parameters like rotational speed, traverse speed, axial force, shoulder diameter, and tilt angle. Tensile test samples were prepared and tensile strength values were measured for different parameter combinations based on a Taguchi design of experiments. Optimum tensile strength was found at 1000 rpm speed, 14 mm/min feed rate, 7 kN axial force, 17 mm shoulder diameter, and 3° tilt angle for cylindrical tools and 710 rpm speed,