The butt welding of 1.4462 (2205) duplex stainless steel plates with thickness of 4 mm under various welding parameters was achieved by Nd:YAG laser type without the use of the filler material. Welding parameters such as welding power (kW) and the focus distance from the joint surface (mm) were changed. The Ar 5.0 protective gas flow and welding speed were the same for all the tests and were 20 L/min and 0.5 m/min, respectively. The weld shape, weld macrostructure, microstructure, strength and hardness, and the content of the ferrite in the weld zone, heat-affected zone, and base metal were emphatically investigated. The test results showed that increase in laser power increases the weld zone area. For the weld samples, a better ferrite/austenite ratio was obtained by focusing the laser beam on the sheet surface. Furthermore, the largest elongation from strength test has been observed for the weld samples made with laser power of 2.0 kW.