Aluminum has good ductility in cold conditions and has a high corrosion resistance. Aluminum is very competitive and widely used in engineering such as shipbuilding, railroad car structures, car and aircraft manufacturing. welding method used in this study is welding GMAW (Gas metal Arc Welding) or MIG (Metal Inert Gas). This study aims to determine the type of porosity defects in MIG (Metal Inert Gas) welding joints. The material used is aluminum series AA 5083 H116 with a length of 300 mm, width 150 mm and thickness of 3 mm. The variables used are variations in welding defects radiographic results and strong currents of 100 A, 110 A and 120 A. The tests carried out are radiographic tests, tensile tests, bending tests and macro observations at the welded joint. Based on the test results obtained by the type of defect at a strong current 120 A is a clustered porosity defect, 110 A is a linear porosity defect and 100 A is a distributed porosity defect. the value of the tensile strength at a current strength of 110 A is 210.76 MPa which is the highest tensile strength value because it has the best weld bead shape among other specimens. The value of bending strength at a current strength of 100 A is 148,873 MPa as well as being the highest bending strength.