Abstract: In order to reduce the dust concentration of underground working face, we propose an energy saving type of high-expansion foam dust suppression device that uses underground coal pressure wind pipe to provide high pressure air as power. Compared with other dust suppression device, it can make the gas and liquid intensively mixing to produce a large number of bubbles and save energy and water. At the same time, based on features of cooperative principle and by adopting compound with orthogonal test, we develop an environmentally friendly foam reagent. It has high stability, strong dust catching ability, no harm to the staff, etc. The field measurement shows that the dust rate of foam generator for total coal dust is 93% and for respirable dust is 79%.