Abstract: The paper analyzed harm and characteristics of coal mine dust and standard of contact concentration of respiratory coal dust in air of working space, introduced developing status of monitoring technology of coal mine dust, and compared characteristics of sampling method and non-sampling method. It pointed out that non-sampling method should be a main monitoring method of coal mine dust and light-dispersion method in non-sampling method is most suitable for coal mine underground. Application of GCG1000 dust concentration sensor based on light-dispersion method in coal mine underground showed availability of the method.