Natural gas pipelines are usually embedded in the ground or seabed, so detecting pipeline leakage is an important issue inits safe operation. In order to effectively do so, a method using a fiber bragg grating (FBG) strain sensor is presented based on hoop strain monitoring. The negative pressure wave induced by pipeline leakage would induce a decline in internal pressure, which can be directly detected by the hoop strain sensor. In this paper, a series of experiments are conducted using the FBG strain sensors, which sample the hoop strain variation data in different tests, including pipeline leakage with different positions at different rates, branch pipeline leakage, and pipeline pump regulation simulations. Experimental results show that the FBG strain sensor can be applied to accurately detect gas pipeline leakage information in real time, showing that the method is effective and promising.