Abstract: Screw drill tool consists one of the crucial parts in the program of Short to Medium Radius Horizontal Well Sidetracking Technology, which lists in the national "Ninth-five-year" plan. Small size bent housing screw drill with high build rate must be developed to meet the requirements of sidetracking the short to medium radius horizontal well. This paper evaluates the advantages and disadvantages between the double bent housing and single bent housing screw drills from many aspects, e.g., the structure equivalent correlation. A model 5LZ95×7.0 integrate double bent housing screw drill has been designed and tested on site, and it proves to be a practical and effective new tool for horizontal drilling.