The invention discloses an agricultural big-data model. A framework of the model is mainly composed of four parts, namely an agricultural data definition part, a sensor part, a data collection part and a data mining analysis part. Three main data streams, namely organization presentation of agricultural data, sensor data and mining analysis result feedback connect the four parts. The data mining analysis part includes data conversion, data integration, database building and mining analysis. Bases of database building and big-data mining analysis are a distributed architecture and a cloud platform. According to the model, data sources of mining analysis are broadened, analysis functions are deepened, and analysis results are more accurate. From the view of a current stage, application of big data in agriculture includes but is not limited to: agricultural visualization monitoring systems, more-accurate short-term, middle-term and long-term disaster prediction, close integration with agricultural remote sensing, agricultural product circulation systems, agricultural meteorology prediction and agricultural environment change trend prediction.