Choice of five polynomial method to construct multiple-sectional linear turbine blades and using bezier curve linear transition each cross-section, which devised a continuous tube job with a small size, high efficiency three-dimensional Cascade turbodrill. Through the flow field numerical simulation and hydraulic cycle test explores the three-dimensional modeling method cascade design of small size turbodrill feasibility of adoption. The results show that under certain cycle of displacement, three-dimensional turbine cascade theoretical maximum efficiency of section 62.88%, the highest hydraulic efficiency test cycle test 54.25%, three-dimensional turbine cascade of water-saving force performance has improved significantly improves the efficiency of drilling work ,reducing drilling costs.