Abstract: Fracture analysis on outlet pipeline of Qihe Pump Station in LuNing Oil Pipeline is made from pipe material and corrosion condition.Analysis results regard that bearing section at external wall of fractured pipe deereased greatly due to soil corrosion, and welding defect existed in weld bead had possibly formed a higher triaxial stress, afterwards brittle rupture was produced and progressively developed and at last fractured.It is considered that integrity management and evaluation of pipeline should be carried out at the right moment combined with actual operation of pipeline.