Abstract: Having being in operation for 20 years, Golmud-Lhasa Products Pipeline suffered from grievous coating damages due to unfavorable environment, complex geology and artifacial destructive activities. In a period of four years and at a cost of 1.08 million RMB, the second leak inspection and repairing over the 1, 080 km pipeline was made, and 14, 236 leak points discovered, excavated and recoated per new specifications with construction method, techniques and expences as well as pipeline corrosion information described in detail. The following reasons for coating damages are introduced: ① soaking with salty water, ② wheathering, ③ repeatative rolling by construction machinery on Qinghai-Tibet Highway, and ④ poor coating quality. After leakage repairing, the pipeline performances were recovered, and scientific experiences provided for pipeline management and production planning.