Abstract: Luokexiu foam is a kind of expansive resin product,it is suitable for the packing of the mass caving zone in complicated geological conditions for its merits such as high reaction speed,the huge expandable volume,the stable chemic quality and its good bearing capability,etc.This paper presented the packing technique for heavy roof falling zone through one of its applying instance;In the field practice,the collapsed zone rock mass was controlled successfully,the technology has gained good total efficiency with its easy operation,high working speed,being suitable to safe working,etc.The engineering case also showed that the new packing technology was an effective way to deal with the similar mass-caving instance.