Self-sensitized FOX-7 (1,1-diamino-2,2-dinitroethylene) was prepared by a facile heat treatment process near the decomposition temperature. Field emission scanning electron microscopy (FE-SEM) shows the self-sensitized FOX-7 becomes multiple layers and porous after heat treatment. N-2 adsorbance measurements revealed that its specific surface area (6.754m(2)g(-1)) is 20 times of the area of expanded ammonium nitrate. The SAXS tests further indicate the existence of a large amount of voids in self-sensitized FOX-7 and the pore size is about 30nm, belonging to mesopore (2.0-50nm). Based on the analysis of X-ray powder diffraction (XRD), the self-sensitized porous FOX-7 consists of -phase and a spot of -phase. The TG-DSC results show that the self-sensitized FOX-7 exhibits excellent thermal stability. The impact, frication and electrostatic spark sensitivities of self-sensitized FOX-7 also have considerable enhancement. This new method provides a promising route for exploring new green primary explosive replacements.