Abstract: Based on analysis of present subirrigation system, this paper discusses the feasibility and mechanism of irrigation and drainage of underground soil base osmosis pipe. The prototype which can finish integratally the work of making the shape, strengthing the wall, preventing the water leach and inlaying the leaching strip in once operation, was developed and verified through field experiment. The mechanism of making shape of the machine was analyzed. It is shown that underground conjunctive irrigation and drainage pipe hasmore advantages than other saving water irrigation. It is possible that this kind of pipe will be an advanced, practical technology in farm land irrigation and drainage because some key problem were solved.