The invention discloses a portable pipeline automatic circumferential walking device and a pipeline processing method, which belong to the technical field of pipeline processing and construction. The portable pipeline automatic circumferential walking device consists of a circular rail, a walking mechanism and a control part. The circular rail consists of a rail and a grab for mounting the rail. The portable pipeline automatic circumferential walking device has the characteristics that one type of rail is adaptable to a plurality of types of pipe diameters, and a plurality of types of rails is adaptable to more pipe diameters in a matching mode. The walking mechanism consists of a machine frame, wheels, a chain tensioning mechanism, a driving motor system and a chain. The control part consists of a local controller and a remote controller. The local controller can adjust positive rotation and negative rotation of a motor, and can adjust the walking mechanism to perform clockwise rotation or counterclockwise rotation around a pipeline. The remote controller can control the walking mechanism at a distant place, and is compact and convenient. The portable pipeline automatic circumferential walking device is convenient to mount, has high walking accuracy, is not affected by whether the pipeline has a coating layer or not, and is suitable for meeting requirements on circumferential construction of an onsite pipeline.