Abstract: Commingled producing strings with separated layer fracturing by packer is commonly used in multilayer production of Sulige gas field, which is featured by large tube diameter, poor liquid carrying ability for water-bearing gas zone, great risks of fractur-ing operation and not accustomed to separated layer fracturing in slim hole. Integrated technique of turning annulus separate layer to fracturing commingled producing in slim-tube with sandblasting perforation was studied and matched. The technique involves in a series of techniques such as sandblasting perforation in slim-tube, separated layer fracturing in annulus between tube and casing, sec- ondary deflection fracturing and down-hole choke in slim tube. The whole treatment process of sandblasting perforation and separate layer fracturing and commingled producing was accomplished by using slim diameter string once, which greatly enhanced the liquid carrying ability of strings. With the technology, the effect of fracturing stimulation is improved, and the risk of fracturing construction is decreased. Meanwhile, less string cost, shorter construction period and well performance of separated layer fracturing in slim hole are also very impressive. Good results have been obtained in filed application, and the success is worthy further application and extension.