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In this research, the experimental and numerical analysis of the Al. alloy 5083-H321 fracture behavior under uniaxial and bi-axial tension has been investigated. The bi-axial tension cruciform specimens are made by electrochemical methods, according to Lionel model, for considering bi-axial fracture behavior of the material. The specimens are gridded by electrochemical etching method. A dependent bi-axial tension mechanism is fabricated with relatively high precision machining methods. The experimental bi-axial tests have been performed by the mechanism on the INSTRON-1343 uniaxial machine, at ambient temperature and strain rate of 0.0003 1. For comparing the experimental and numerical results, how to fracture the material at the beginning and development of it, the location of fracture on the test section of cruciform specimen, and the force diagrams on the cruciform specimen arms are of interest can be mentioned. The finite element method has been used with regard to the damage conditions of ABAQUS software for simulating the fracture behavior. The experimental results show that fracture at the specimen center does not happen. The fracture of cruciform specimen begins in the test section of specimen and in range with the corners of the specimen. Furthermore, the strains are minimal near cruciform specimen arms and in the test section area. Also, the gradient of stress is towards the test section and along the corners. There was an excellent correlation between theoretical and experimental results for location of damage initiation in the test section, how to fracture in the beginning and after that, and arms forces.