Double-bend screw refers to the drilling tools combination form of bending joint and bend housing screw. The use of double-bend screw for hole straightening can get larger built-up rate to solve the difficult straightening while using the single-bend screw in some specific conditions. Selecting proper angle of bend joint and shortening deflecting distance of double-bend screw are important factors to control dogleg angle, which can ensure later work of smooth reaming and casing. Take the straightening case in a large diameter drilling, the difficulties encountered in straightening with single-bend screw are listed, by the analysis on the deflecting effect of double-bend screw, a set of straightening technology with double-bend screw is put forward and successful borehole straightening is finally realized.