Abstract: The remaining oil of complicated faulted-block reservoirs in Shengli Oifield distributed dispersed in the mid-late development stage. Using abandoned resource and sidetracking in old wells to recover the highly dispersed remaining oil in inter-well stagnant area and local structural high is an effective means to enhance the recovery ratio of old oilfields. As some problems are exposed during the completion and production process of sidetracking wells such as small inner diameter, inadequate perforation depth, difficult zonal production, and low casing strength resulting from using tubing as casing, the research and application of the matching technologies including new small-diameter (Φ95mm) casing completion technology, small hole mechanical packer plugging technology, chemical plugging and channelling plugging technology have been introduced in this paper and they were popularized in site.