Abstract: Irrigation water optimization distribution plays an important role in improving irrigation management. A few of models and softwares were developed, but most of them need a lot of parameters and are designed for special irrigation system, thus it is often difficult to use in practice. In this paper, a general irrigation water distribution model that has less input parameters and stable calculated results is put forward and a model calculation method based on genetic algorithms is presented. The method is coded with the order number of alternative irrigation canal so the length of chromosome in genetic algorithms is cut down and the calculation is speeded up remarkably. Based on the model and algorithms, a general software for irrigation water optimal distribution was developed on the platform of VC++6.0. By use of irrigation canal layer CTreeView map, simplified canal space-layout map and canal parameter database, the software can directly demonstrate the complex linkage of upper and lower irrigation canals, space-layout structure and canal characteristic parameters of an irrigation system. The maps and the database above are linked dynamically, users can easily edit the complex irrigation system structural and space-layout map, modify the characteristic parameters of irrigation canals. The software is easy to operate, when inputting the requirements of irrigation water distribution, it can automatically transfer the relative canal characteistic parameters from the canal character parameters database to model computing program and then output the results of irrigation water optimal distribution. The software with visualized manual interface can be widely used in decision-making in irrigation water optimal distribution.