Abstract: The anti-fracture property of oil and gas pipeline is vital important to the safety and reliability of pipeline transportation system. This paper introduces a computer-aided assessment system developed by the authors, which can be used in evaluating the fracture property of oil and gas pipeline system. The study shows that the factors such as fracture toughness, mismatch between base metal strength and weld strength and the initial crack condition have remarkably effect upon the fracture assessment of oil and gas pipelines 'joint welds. The study results provide a scientific fundamental to fracture assessment of oil and gas pipeline.