The survey on the invertebrate in caves of Ba Be National Park and the extension area was carried in two times, the 1st time in April 2011, the 2nd time in August 2011. The survey were done in 15 caves (Tien cave, Puong cave, Na Phong cave, Tham Thinh cave, Hua Ma cave, Ban Pjac cave, Khau Qua cave, Coc Toc cave, Ba Cua cave, Tham Kit cave, Ban Pjan cave, Bup Lom cave, Tham Liem cave, Y te cave, Huoi Giong cave). The survey result were collected 472 individuals including 55 families of 7 classes, 24.orders in caves of Ba Be National Park. The large and long caves with a complicated structure with many corners are more valuable in term of biological diversity than the small caves with a simple structure. The main differences in faunal assemblage shown by the current survey are the dramatic differences in faunal diversity and abundance between areas used by tourists and the wild sections of the same caves. Most of the invertebrates are found in the wild sections. In addition, all of the species intended to be new taxon are found in the wild sections.