A pipeline leakage detection system and a method thereof are provided. In the pipeline leakage detection system, when a ball-type detection device is operated on a pipeline and moved by an external force, a processing module can, according to angular velocity data outputted by a posture detection module, control motors to drive wheels, so as to prevent a ball-type casing of the ball-type detection device from being rotated by the external force; a wireless transceiver module transmits thermal image signals around the pipeline captured by multiple infrared thermal imagers to a monitoring terminal; and the monitoring terminal combines the thermal image signals, according to a sequential order of pieces of time information of the thermal image signals and pieces of identification information of the infrared thermal imagers, to form multiple time images, and the monitoring terminal can analyze the time images to determine whether the pipeline has a leaking location.