Abstract: Abstract: Few studies have been done on the layout of ditches, and the quantitative models for the optimization of the channel layout is lacking. Since the cost of channel layout project accounts for a large proportion of the cost of land reclamation project, it is necessary to find a design in order to reduce the cost of channel project. In this paper, a new model was developed for optimal layout of canals and ditches. The theory of minimum spanning tree was used to describe the channel layout of land reclamation project, and an optimal model based on minimum spanning tree theory was established in combination with the virtual point, the alternative water intake point and the weighted definition node. The study area was located at a coal mining subsidence area in Yongqiao District, Suzhou City, Anhui Province (33°24?-33°25?N and 117°3?-117°5?E). The channel optimization layout model based on the minimum spanning tree was constructed to optimize the layout of farmland irrigation channels in the plain areas. Different from the traditional minimum spanning tree model, this model solved the optimization problem for two-level channels, and the final solution using this model was greater than or equal to a minimum spanning tree. In order to take advantage of the mature minimum- production-tree approach, the virtual point concept was created to eliminate the difference between the channel optimization layout model and the traditional minimum spanning tree model. Four cases of solving the model were discussed by convex hull theory. The LINGO program was written for solving the model. Finally, the channel optimization model based on the minimum spanning tree was applied to a research area, and then the channel layout scheme using this model was obtained with a total length of 20 523 m containing 1 lateral canal (2 811-m length) and 22 ditches (17 712-m length). According to the traditional optimum principle, there were totally 20 572 m with 2 lateral canals (6 037-m length) and 23 ditches (14 535-m length). The lateral canal was designed as a trapezoid for the land reclamation with a mouth width of 150 cm, a base width of 50 cm and a depth of 100 cm. The ditch was designed as a rectangle with a mouth width of 80 cm and a depth of 90 cm. For the lateral canal, the engineering workload of unit length was 1 m3 and for ditch engineering workload per unit length was 0.75 m3. The unit length engineering workload of the lateral canal was 1.33 times of the ditch. Based on unit length engineering workload mentioned above, the total engineering workload of the land reclamation project was 16 095 m3 by using the channel optimization layout method based on minimum spanning tree and 16 938.25 m3 by using optimum principle method, respectively. The engineering workload of the minimum spanning tree method was 5.0% less than that of the optimum principle. According to the unit price of the lateral canal engineering project 85 yuan per meter and the unit price of ditch engineering 49.58 yuan per meter, the project cost of 116 694 yuan was saved. The result shows that the channel optimization model based on the minimum spanning tree can obtain the channel layout plan with less cost, that is, the maximum control of land reclamation cost. This study can provide an effective way to cost control of land reclamation projects.