Abstract: According to the development characteristics of deep-water oil field, combining with the development and production needs of L oilfield in the eastern South China Sea, a well completion production string technology was designed to control the flow rate of the two production layers with a hydraulic control sliding sleeve. The flow aperture of the hydraulic control sliding sleeve was selected and optimized, and the ground control logic was designed. The tandem hydraulic control sliding sleeve completion string technology has been successfully applied to L oilfield, which has important reference significance for follow-up reservoir development.