Abstract: Objective According to the free radical theory for aging, to establish the simple and easy method for brain-aging model, providing theory for brain-aging mechanism and clinic prevention and therapy. Methods The acute brain-aging model was established by ₆₀Co radiation, the second-acute one was established by injection of D-gal, and 5-monthly SD rats as the young control group. The rats， learning and memory ability was determined by Y type labyrinth, the rats’ antioxidant and lipid peroxidative injury were measured by SOD and MDA in blood. The neuron’s lose, injury and degeneration were observed with microscope. Results We found the descend of brain aging rat’s learning and memory ability with Y type labyrinth；The blood’s SOD in brain-aging model was significantly lower than that of the control, the MDA content in brain-aging model was markedly higher than that of the control； The neuron’s lose, injury and degeneration were observed by microscope in different brain region of the rat model, especially in cortex and hippocampus mostly. Conclusions The acute brain-aging rat model can be established simply and easily by radiation.