Survey on invertebrate biodiversity of volcanic caves in Krong No, Dak Nong province, Vietnam was carried in 2018 and 2019. The survey were done in 8 typical caves are Co cave (475 m long), C1 cave (402 m), C2 cave (402 m), C3 cave (716 m), C4 cave (251 m), C6 cave (180 m), C6.1 cave (293 m) and C7 cave (1066 m). The survey result recorded 41 species, 31 families of 5 classes, 13 orders of invertebrate at volcanic caves in Krong No. It is expected that 13 species will become new taxa, for example a scorpion of the Chaerilidae family, Chaerilus chubluk Lourenco, Tran & Pham, 2020 in the Co cave. 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.