In the present study, the joining of AA 6063-T4 aluminum was carried out by friction stir welding (FSW) technique using two different tools such as conical shoulder and scrolled shoulder at two tool rotational speeds of 900 rpm, 1400 rpm and transverse speeds of 125 mm/min, 165 mm/min. Prepared FSW welds were analyzed and compared mechanical properties. For each tool welding parameters were optimized to achieve non defective welds. The obtained results indicated that conical shoulder tool joints has superior properties compared to scrolled shoulder FSW welds particularly when the tool rotating speed 900 rpm, welding speed 125 mm/min are applied.