To research the influence of the additives such as RDX， Al， AP and polymer PBNMO on the moulding and mechanical characteristics of DNAN， the crystallization process of different intermixtures and the initial solidification temperature were observed mainly by photic microscope. The solidification rate was calculated by measuring the solidification time and the distance change. The effects of additives on the molding process were studied by testing the relative density of the Φ20 mm samples. The effects of additives on the mechanical properties were studied by testing the tensile strength and the compressive strength. Results show that those additives could improve the crystallization process， increase the relative density and decrease the solidification rate of DNAN. The mechanical properties such as the tensile strength，compressive strength and the anisotropy of the DNAN were improved by adding polymer PBNMO. The tensile strength was over 6 MPa. The results showed that， DNAN based explosives with fine crystals， less defects and better mechanical properties could be got by the synergistic effects of RDX， Al， AP and PBNMO.