In this experimental work the weldability of an Al alloy AA 2024-T3 by using two different laser sources, (CO2 and Nd:YAG), has been tested for experiments. A ROFIN SINAR, 1500 W continuous wave (c.w.) max power level, emitting at 10.6 μm, and a HAAS TRUMPH source, 3000 W max power level, pulsed beam, that produces na 1.06 μm wavelength have been used. The thicknesses employed are 0.8-1.6 and 2.0 mm for the Nd:YAG, 1 and 1.6 mm for the CO2. In order to define a possible laser welding process optimisation versus the best quality and relative mechanical properties of the butt joints, different laser working parameters have been studied and experimented. Moreover two diverse welding techniques, that is by using a filler wire or without one have been applied and the relative results have been compared. The best selected butt joints have been cahracterized by some visual examinations, micro and macrographs of transverse sections, micro-hardness data and plots as well as some tensile tests. Finally, according to the results as above, physical-technological evaluations and comparisons have been reported.