This work deals with energy performance calculate results of new solid composite propellants based on Hexanitroethane (HNE) and Hydrazinium nitroformate (HNF). The energy characteristics of solid propellants with HNE and HNF are estimated using NASA Chemical Equilibrium with Applications (CEA). The effect of HNE and HNF as energetic oxidizers on the energy characteristics of composite modified double-base (CMDB) propellants, hydroxyl-terminated polybutadiene (HTPB) propellants, nitrate ester plasticized polyether (NEPE) propellants, glycidyl azide polymer (GAP) propellants has been carried out. Characteristics of ingredients and propellant formulations with HNE and HNF are presented together with the calculate results which demonstrate the increased performance compared to conventional high-performance propellants based on Ammonium Perchlorate (AP). The results show that HNE and HNF can improve the standard theoretical specific impulse of the four propellants in different degrees, and HTPB propellant has the most significant improvement, which is 12.26 s for HNE-based propellant and 14.12 s for HNF-based propellant. At the same time, both HNE and HNF reduce the infrared emission of propellant exhaust plumes when they replace AP, and reduce or even completely eliminate HCl gas in exhaust products. Therefore, it is expected that HNE-based and HNF-based propellants may provide a promising chlorine-free alternative to existing AP-based formulations.