Abstract: Based on the characteristics of Weijiadi Mine soft coal seam, taking East 102 fully mechanized caving face as the research object, dust movement laws of fully mechanized caving face are studied by numerical simulation and field measurement. The coal dust concentration is largest in range of the down wind 20 ~ 30 m when shearer cuts coal; the dust concentration is largest from the support 10 ~ 20 m during moving support; and the dust concentration is largest at caving mouth during coal caving.