The invention relates to a method for super-plastic pretreatment of an in situ aluminum base composite material. The method comprises the steps of performing forging plastic deformation on blocky in situ aluminum base composite material ingots to prepare an in situ aluminum base composite material plate with a certain thickness; linearly cutting the in situ aluminum base composite material plate into a regular shape; performing friction stirring processing on the linearly cut plate material; then performing high-temperature drawing to realize super-plasticity. According to the method disclosed by the invention, through large plastic deformation of combined processing of forging and friction stirring, the sizes, shapes and distribution of particle reinforcements of the in situ aluminum base composite material are improved, and matrix crystal grains are fully refined, thereby realizing the super-plasticity of the in situ particle reinforced aluminum base composite material. Experiments show that the high-temperature elongation of the in situ aluminum base composite material treated by the method disclosed by the invention can reach more than 100%, the super-plasticity of the in situ aluminum base composite material is realized, and the high-temperature processability of the in situ aluminum base composite material is improved.