The invention relates to a device for detecting the leakage of an oil-gas pipe network based on type-2 fuzzy logics and a method. The device comprises a data acquisition unit, a signal filtering plate, an A/D (Analog to Digital) conversion unit, an FPGA (Field Programmable Gate Array), a level conversion unit and an upper computer, wherein the data acquisition unit comprises a pressure sensor, a flow sensor, a density sensor, a digital sensor which is used for acquiring the state of a pump and a digital sensor which is used for acquiring the opening degree of a valve; the signal filtering plate comprises a filter, a multi-way switch and a signal amplification circuit; and output terminals of all the sensors and an output terminal of the digital sensor which is used for acquiring the opening degree of the valve are all connected to an input terminal of the filter, an output terminal of the filter is connected with one terminal of the multi-way switch, the other terminal of the multi-way switch is connected with an input terminal of the signal amplification circuit, an output terminal of the signal amplification circuit is connected with the FPGA through the A/D conversion unit, and the FPGA is connected with the upper computer through the level conversion unit. According to the device and the method, the leakage detection on the oil-gas pipe network is carried out by adopting a type-2 fuzzy logic system, the current state of the pipe network is judged, and thus, the accuracy of detection can be improved.