A field crop irrigation management decision-making system (CropIrri) was developed based on the soil water balance model, crop phenology model, root growth model, crop water production function, and irrigation management model. The irrigation plan is made through predicating of soil water content in root zone and daily crop water requirement using historical and forecasting weather data, measured real time soil moisture data. CropIrri provided four decision modes of non-limiting irrigation, water-saving irrigation, irrigation with experience and user custom irrigation. The main function of CropIrri includes: pre-sowing and real-time irrigation management decision-making support, simulation of soil water dynamics in the root zone, evaluation of the effect of certain irrigation plan on crop yield reduction, and database management. A case study of wheat crop irrigation management by CropIrri showed its practical value and benefit. It could be an objectives-oriented, multi users-oriented and practical irrigation management decision-making tool.