A series of ionic liquids based on N，N-（dimethylcyclopropyl）cyclopropylamines as cations and dicyandiamide/cyanoborohydride as anions were synthesized by using the three-member carbocyclic ring as the tension energy structural unit. The structures of ionic liquids were confirmed with the characterizations such as nuclear magnetic （NMR）， infrared spectroscopy （IR） and high-resolution mass spectrometry （HRMS）. Their physicochemical properties （e.g.， melting point， thermal decomposition temperature， density， viscosity， heat of formation， specific impulse， and ignition delay time） were measured and/or calculated in detail. The results demonstrate that all ten synthesized ionic liquids show hypergolicity with white fuming nitric acid （WFNA）， and the cyanoborohydride based ionic liquids have the shorter ignition delay times than the corresponding dicyandiamide ionic liquids. More strained ring groups lead to the higher heats of formation （0.87-1.96 kJ·g^-1）， and the compact stacking of small ring structures makes an increase in the densities （1.01-1.18 g·cm^-3） of the ionic liquids. Therefore， the strained ring-based hypergolic ionic liquids exhibit the higher density-specific impulse （436.7-454.4 s·g·cm^-3）. The introduction of high-energy strained ring groups in the molecular structures provides a way to improve the energy densities of hypergolic ionic liquids.