Abstract: A model was constructed in laboratory to simulate the acoustic emission pipeline leak detection. Under different test condition, such as changing the pressure of liquid, the size of leak hole, orientation of sensors, distance etc, the experiment of acoustic emission pipeline leak detection was implemented. From the analysis of the acoustic emission signal, whether the pipeline was leaky could be judged qualitatively, and the relationship respectively between the acoustic emission signal and pressure, hole size, sensor orientation, distance, etc. was also studied. The qualitative investigation provides groundwork for quantitative investigation of the acoustic emission pipeline leak detection.