The utility model provides a natural gas pressure regulating skid mounted unit with multistage safety protection function, vapour and liquid separator and many pipelines on prize the seat, locating the sled seat, many the pipeline includes air inlet pipeline, pressure reducing pipe way, first output branch road, second output branch road and travels empty total pipeline. Be equipped with an emptying pipeline between urgent shut -off valve and first air -vent valve, when the circuit superpressure, promptly travel empty through first relief valve, be equipped with the 2nd emptying pipeline between first gate valve and vapour and liquid separator, when the circuit superpressure, promptly travel empty through the second relief valve, be equipped with manual unloading before with the gas port getting into low reaches, when the circuit superpressure, open the gate valve and the stop valve emptys.