Abstract: Land improvement for middle and low yield farmland in the diked area of Huaihai farm were carried out during 1992 1997. On the basis of making full use of existing water conservancy facilities, reformation of the irrigation and drainage systems of farmland were made, especially for those with outstanding drought, alkalie and water logged conditions. Several problems related colosely to technique and economy in planning and design were discussed. The experiences in improving middle and low yield fields are introduced in this paper.