Abstract: After five times experiments of coal gas pressure measurement in Yuntaishan area, Shanxi Province, the structure, working principle and measurement procedure of the drill gas pressure measuring apparatus are introduced systematically. On this basis, a complete mature measurement experience of managing the mud quality for measurement pressure, raising plugging effect and Seiaing accurately the point of reducing pressure is sumed up. After analysing the measurement principle, function of main parts, high success rate and economic benefit of the apparatus, it is concluded finally that the apparatus is available for use in the coal geology system of our whole country.