Marine caves are considered an important and endangered habitat type and they are listed in Annex I of the EU Habitat Directive as one of the priority habitats. Here, a synthetized knowledge on this type of habitat in Montenegro is presented. The biodiversity data include 23 marine caves hosting more than 250 species. The main threats are physical damage (caused by divers and new infrastructure building), disturbance of the species (by marine litter and noise), non-indigenous species and climate change. Further research is needed in order to better document the biodiversity of marine caves, fill the gaps in knowledge of completely submersed caves and establish appropriate monitoring and management of this specific habitat.