Abstract: The aluminum alloy cylinder section of aerospace product is welded by the friction stir welding, and the internal quality of the welds needs to be inspected by radiographic testing to ensure product quality. Industrial film radiographic inspection has problems such as low inspection efficiency, difficulty in storing films throughout the life cycle, and restrictions on the discharge of developing and fixing solutions as hazardous waste, which cannot meet the requirements of large-scale inspection and environmental protection. This paper focused on the micro-focus digital radiography testing technology, combined the characteristics of the welds, systematically carried out inspection process parameters optimization experiments, including the tube voltage and tube current, optimal magnification, radiography layout, etc., and compared it with the inspections effect of industrial film radiography to verify the reliability and efficiency of the micro-focus digital radiography inspection results.