To prepare nanocomposite energetic materials with homogeneous structure and excellent thermal properties, CuO/Al nanocomposite energetic materials were prepared by deoxyribonucleic acid (DNA) self-assembly method at room temperature and in water phase. The structures and thermal reaction properties of the nanocomposite energetic materials were characterized by Fourier transform infrared (FT-IR) spectroscopy, dynamic light scattering (DLS), transmission electron microscope (TEM), scanning electron microscope (SEM) and differential scanning calorimeter (DSC). Results show that CuO/Al nanocomposite energetic materials with more homogeneous structure are successfully prepared by DNA self-assembly. The reaction heat of DNA self-assembled CuO/Al nanocomposites is higher than that of physically mixed sample with the same proportion and at φ=1.6, the reaction heat of DNA self -assembled CuO/Al nanocomposites reaches 1520 J·g^-1，which is 52.15% higher than that of the physically mixed sample (999 J·g^-1).