With the rapid development of China's economy, the traditional coal energy demand is increasing. But most of China's coal mines are underground, high concentrations of gas, mining more difficult, technical requirements, in the slightest mistake in the mining process, it could trigger a major accident, a gas explosion in China coal mine safety has become the "first Killer. " Therefore, the coal mine gas concentration in real-time monitoring of particular importance. The subject of gas through the gas monitoring mechanism analysis, to Visual Basic 6.0 for development tools, using C / S software development model, the establishment of SQL Server2000 database as a platform for gas monitoring system. The system's design and development process, giving full consideration to the mine gas monitoring the needs of gas, the gas concentration to achieve real-time data collection, database management and gas to the monitoring data processing. And to achieve a gas monitoring information on a monthly, quarterly and annual actual changes in the display interface and data statements, according to data collected by the gas to map out changes in the trend curve, the unusual situation of the data generated warning. Related personnel can grasp the system time to change the concentration of gas underground, mine gas against the defense work to provide strong technical support.