a composite , supported microporous medium is provided which includes a fluoropolymeric microporous membrane having secured directly to at least one surface thereof a fluoropolymeric web of microfibers . a method of forming a composite , supported microporous medium is also provided which includes contacting a fluoropolymeric microporous membrane with a fluoropolymeric web of microfibers and subjecting said fluoropolymeric membrane and web of microfibers to sufficient heat and pressure to effect bonding therebetween . the composite , supported microporous medium may be employed for separation of a particulate material from a particulate - containing fluid . the composite medium also finds use in analytical procedures .