A simple and efficient synthesis of face-centered cubic (FCC) copper nanocrystal particles (Cu NPs) was presented by the gaseous detonation method which used the hydrogen-oxygen gases mixture as the explosion source and the copper (II) acetylacetonate as the precursor. The morphology, phase constitution and microstructure of the as-obtained products were analyzed by XRD, TEM, SAED and EDX. Meanwhile, to predict the growth characteristics of the Cu NPs, the Kruis model was tentatively integrated in reaction condition of gaseous detonation. The results showed that the as-synthesized FCC structural nanocrystalline copper with good dispersibility was coated with thinner graphite layer and the average size of particles was 24 nm. In addition, the growth characteristic of spherical Cu NPs was in consistent with the obtained experimental data based on Kruis model, which provided reliable theoretical guidance for the controllable synthesis of Cu NPs.