The invention provides a positioning system, device and method of a pipeline cleaning device. The system comprises a transmitter, a plurality of receivers and a positioner, wherein the transmitter is fixed on the pipeline cleaning device and used for transmitting at least two electromagnetic signals with the same amplitude and different frequencies, the receivers are arranged along an oil gas pipeline and used for detecting the electromagnetic signals with the same amplitude and the different frequencies and sending the position information of the receivers to the positioner when detecting the electromagnetic signals, the electromagnetic signals are sent by the transmitter, the positioner is used for receiving the position information of the receivers and determining the position of the pipeline cleaning device according to the position information. Whether the pipeline cleaning device is detected or not is judged by transmitting and detecting the electromagnetic signals, a large amount of electromagnetic interference existing in the testing environment can be effectively removed, the false alarm rate is greatly reduced, the positioning accuracy rate of the pipeline cleaning device is obviously improved, and better service is provided for the pipe cleaning operation of the oil gas pipeline.