The invention relates to metal surface shot peening strengthening, in particular to a shot peening strengthening process method for a fracturing pump valve cavity. The method is characterized in thata rotary vane with tungsten carbide shots adhering to rotary vane is clamped by using a hand-held pneumatic or electric rotary motor, and rotary vane shot blasting is adopted for the fracturing pump cavity. The process method comprises the following steps of selecting a shot blasting tool, carrying out shot blasting process on a test piece, implementing a pump valve cavity shot peening strengthening process, carrying out inspection and carrying out pump valve cavity shot blasting post-treatment. According to the method, certain residual stress distribution can be formed on the inner wall surface of the fracturing pump cavity capable of easily generating a fatigue failure area, and therefore the bearing capacity of a pump valve box is enhanced, the fatigue life of the pump valve box is prolonged, in addition, the operation is simple, and the equipment investment cost is low.