Pipeline leak detection technology is so important that it guarantees the normal operation of long-distance oil & nature gas pipeline. Summarized and introduced briefly are domestic and foreign pipeline leak detection technologies. At present, the technologies which can be applied to continuous on-line detection mainly include Real Time Transient Model, Sequential Probability Ratio Test, Negative Pressure Wave, Fiber Optic Cable Detection and Acoustic Emission Detection. In particular, discussed are principles, advantages and disadvantages and engineering application of the five detection technologies and conducted is contrastive analysis on false alarm rates, size of the leak holes and leak positions of these technologies and analysis results can provide valuable reference for selection of leak detection technologies.