For monitoring range limitation of current single-substation micro-seismic monitoring system, a KJ699 micro-seismic monitoring system based on multi-substation was developed. The system uses multi-substation clock synchronization technique, introduces concept of mine-wide and extends monitoring range from one coal face wide to mine-wide. Meanwhile, the system optimizes location method of micro-seismic focus by use of velocity calibration and optimal channel selection technology based on the mine-wide monitoring scale. The field test result shows that the system can monitor a wider range micro-seismic, and enhances location accuracy and automation capability, which can provide better basic information for seismic activity analysis, risk assessment and pre-warning of rock burst.