Silicon carbon nitride (SiCN) presents good performance at high temperature while it is difficult to ascertain the chemical structure of its nanodomain by experimental techniques. In this work, empirical potential based large-scale atomistic simulations are used to generate the amorphous structures of SiCN. The models obtained by melt-quench simulations reproduce the nano-domain structure of SiCN and the corresponding PDFs consist with previous DFT calculation and X-ray/Neutron Diffraction experiments. The calculated Young's moduli are comparable to the range of 160-240 GPa in experiments, moreover, it increases with an increasing SiC content and decrease with temperature increases. (C) 2013 Elsevier B.V. All rights reserved.