Abstract: The resistivity recovery experiment is an effective method to study material irradiation damage, and the change of defect number in the material can be characterized by this way. In this work, a dynamics simulation program based on mean field theory was constructed to simulate the evolution of irradiation defects. By using this code, the evolution of irradiation damage of 3 MeV electron-irradiated high purity iron (2.0×10^-6 dpa) under isochronal annealing was simulated. Compared the simulated result with the experimental data, it can be shown that the evolution of irradiation defects with the increasing temperature has a good agreement with the change of the resistivity, and the peaks of resistivity recovery are corresponding to the evolution of interstitial, interstitial clusters and vacancy clusters respectively. This method has a great significance for research of material irradiation damage.