Abstract: Roadheader, as the core equipment of coal face, is very vital to be condition monitored and fault diagnosis.Otherwise there is lack of suitable equipment, the research is still in the phase of simulation.By build the large capacity data recorder,condition signals of underground working roadheader can be collected.After this, we specific analyze the vibration signal, count the dimensionless index , select of kurtosis index and margin index and adopt trend of equipment management method. Then the machine vibration signal of cutting arm alert level and risk level have been determined and simple fault diagnosis method of underground roadheaderis proposed.