Thanks to the development of different materials (in type and grade) and due to a matter of optimizing the selection of materials (in properties and costs), the concept of dissimilar welding arises, which is associated with welds between different steels. The objective of this work is to study the microstructure and mechanical properties of dissimilar welds between plates of austenitic stainless steels (AISI 304L), lean duplex (LDX 2101) and duplex (DX 2205), by using the semiautomatic process with protection inert gas and double pulsed arc, using as filler material a solid duplex stainless steel wire. For this purpose, three welding coupons (A-L; AD ; L-D) with double pulsed arc were welded and cross sections were made for chemical and microstructural characterization, using optical emission spectrometry, light microscopy and scanning electron microscopy, respectively. For mechanical characterization, hardness sweeps were performed on the cross sections, and tensile specimens were mechanized and tested at room temperature. The obtained mechanical results show a significant decrease in the hardness in the heat-affected zone of the austenitic steel and a greater tensile strength in the dissimilar weld between L-D.