Abstract: The paper introduced mechanism of spraying for dustfall and analyzed important influence factors on effect of spraying for dustfall. It designed an intelligent control system of spraying for dustfall in coal mine tunnel. The control system uses dust concentration sensor to detect dust concentration and adopts single-chip microcomputer to compare set standard values of dust concentration with online monitoring values of dust concentration, so as to control spraying for dustfall. If the dust concentration is out of limits, the single-chip microcomputer sends spraying instruction; if the dust concentration is below the standard values, the single-chip microcomputer sends instruction of stopping spraying. The test results show that the system realizes function of automatic control of spraying for dustfall with convenient to debug and good effect of spraying for dustfall.