Gem-dinitro group is an attracting moiety in designing novel high energy density compounds due to their high density and oxygen content comparing to the nitro group. The planar structure of gem-dinitro group is beneficial to improve the density， oxygen balance and detonation properties when cooperating with nitrogen-rich heterocycles. In this review， the method of preparing gem-dinitro salts from different precursors was listed， the advantages of using N₂O₄ or N₂O₅ or mixed acid as the nitration agent to prepare gem-dinitro compounds and their scopes of application were summarized， their energetic characteristics were discussed. It is hoped that this review could provide reference for the design and synthesis of new high-energy insensitive energetic materials.