Abstract: To accurately, quick and automatically determine the airflow velocity and airflow rate in a tunnel, gas permeability of coalseam, gas flow velocity and flow rate in a borehole as well as the influencing radius of borehole due to gas drainage from coalseam, intelligent instruments have been successfully developed based on single chip microcontroller 80C31 that can be used to achieve data collection, analysis and display output. The multi parameter instruments can be widelly used in coal industry, metallurgical industry, air condition and ventilation and exploitation of coal gas, etc.