ABSTRACTThe Arthropoda of Australian Caves are reviewed and assigned to four ecological categories: trogloxenes, first and second level troglophiles, and troglobites. It is shown that Australia has few troglobitic species and this supports an earlier suggestion that extensive secondary extinction of cavernicoles occurred during the Pleistocene and Recent epochs as a result of climatic change. It is further suggested that flooding of Australian caves during the Pleistocene followed by dehydration through general changes in water table levels or through geomorphological change also played a part in this secondary extinction. However, the general climatic changes were probably also responsible for the development of the large number of second‐level troglophiles through extinction of their surface‐dwelling progenitors.