The invention discloses a forging method of an automobile aluminum alloy control arm. According to the forging method, an extruded round bar is adopted as a blank, the blank sequentially undergoes themachining processes of first-pass roller forging, second-pass roller forging, flattening and bending and final forging forming after being heated, two passes of roller forging are adopted, so that under the condition that reasonable material distribution and material deformation are met, the situation that irregular bending is caused when large deformation is generated in the local area of the blank in the flattening and bending process can be avoided, then streamline forming of the control arm is reasonable, the situations that the blank is deformed unevenly and the blank is not fully filledare prevented, and the production efficiency can also be improved; and the control arm forged and machined through the method is good in forming, and is free of the defects of folding and shrinkage holes and the like. The forging method of the automobile aluminum alloy control arm is used for production and machining of the automobile aluminum alloy control arm.