The aluminium alloy 5083-H321 sheets are selected for joining through Friction stir welding with a cylindrical pin profile stirring tool. Four different process parameters—rotational speed, traverse speed, tool tilt angle and Initial heating time (dwell time)—have been investigated by conducting experiments using central composite design. Empirical relationship between the process parameters and the response—tensile strength—is developed through response surface methodology. The developed model reveals that traverse speed and dwell time have a more dominating effect on the selected response as compared to the other process parameters.