Abstract: Residual gas is one part of coalbed gas and has an impact on gas saturation in coal.This paper has analyzed and researched residual gas,proximate analysis and coal petrology measurements of approximat 100 coal core samples with different rank and from, different places.It has been concluded that residual gas contents in coals are different with wide range from 0 to 3 m³/t.The ratios of residual gas content to coalbed gas content are greatly variable from 1.5% to 30.0%.Residual gas content is controlled by coal rank,ash content,coal core size and so on.It is directly proportional to coal rank and ash content.