Abstract: With the rapid development of economy and society, the safe operation of long-distance pipeline shall meet much stricter requirements, so pipeline operation companies urgently need a method which can monitor the operation situation of the whole pipeline in realtime or regularly. The Pipeline Logger developed in this paper is simple and convenient to monitor the operation situations of pipelines. The Pipeline Logger is independently designed with smaller size and can be installed conveniently. It can be carried together with pigs or inspection tools of any type, so it can be used in the process of routine pigging operation or internal inspection to measure conveniently the absolute temperature, absolute pressure, three-axis acceleration and three-axis angular velocity inside pipelines. Based on the recorded data, pipeline parameters (e.g. elbow and girth weld) can be calculated by using the independently developed data processing software to monitor pipeline operation situations conveniently, identify larger abnormal points inside pipelines in time and locate the positions of abnormal points. It is of great significance to the safety operation of pipelines.