The 5xx series aluminum alloy is currently widely used in marine construction applications for the fabrication of chemical tankers, offshore and others because it has good corrosion resistance. This study aims to determine the effect of the welding method on the corrosion rate and impact strength of 5083 aluminum. Four specimens of AA 5083 in this observation were preheated until reaching temperature 50 °C, 150 °C, 250°C and 300 oC as the selected variations. Then, welding result were tested by Charpy impact test with different load for determining amount of energy absorbed during the fracture process. After comparing the the impact toughness, the best specimen was conducting the corrosion rate test by using Corrosion Tester 3-Electrode system. The study result show that specimen with 250oC preheat was the highest impact toughness with 0.1593 mmPY corrosion rate result.