The dispersion particle fuel element in which the fuel particles statistically distributed in the background material presents new challenges for the conventional reactor physics methods.Based on the Monte Carlo method,the sub-fine lattice modeling of dispersion particle fuels in neutron transport simulation was studied,and the impacts on the modeling efficiency and calculation accuracy of the lattice sizes were given. The numerical results showed that the sub-fine lattice modeling with optimal lattice size can meet the re-quire...