Caged energetic compounds are the hotspots in the research field of energetic materials due to their high energy and density levels， and the clarification of their thermal decomposition mechanisms is significant to the in-depth study of their detonation mechanisms and the improvement of their thermal stabilities. Herein， the thermal decompositions of energetic adamantanes， cubanes and isowurtzitanes are reviewed according to the clue of their caged skeletons， and the thermal decomposition mechanisms of these three caged compounds are also summarized. The thermal decomposition of energetic adamantanes initiated from the substituents and possessed Bridgehead Carbon Effect. In contrast， the thermal decomposition of energetic cubanes and polynitroisowutzitanes usually started from the C—C bond in the cage skeleton and the removal of nitro groups， respectively. Future research should further enrich the types of caged energetic compounds and carry out systematic study on thermal decompositions of caged compounds， especially the thermal decomposition mechanisms of the caged skeletons.