Abstract: In order to research the damages of plutonium to the human body in the nuclear accident conditions, ²³⁹PuO₂ particles deposition location and deposition rate in the lung bronchium were simulated with computational fluid dynamic method in the paper. The results show that inhaled ²³⁹PuO₂ particles deposit mostly in the first and the second bifurcation of the lung airway. The research can give references to the nuclear measurement concerned in the plutonium and uranium nuclide deposited in the human’s lung airway under nuclear accident conditions.