The internet of things (IOT) in agriculture consisted three layers, including perceive, transportation and application. The perceive layer were used to acquire the information of crops, soil and environment. The transportation layer was used to establish the transportation network of IOT in agricultural by combing the techniques like GPRS, Zigbee, WIFI, Bluetooth and the intelligent networking methods. The process layer focused on the intelligent management of agriculture, including multidimensional information fusion, intelligent decision and automatic control, et al. The key problems, research emphasis and application fields of IOT in agriculture include three layers were discussed in detail and analyzed. The prospect and development trend of IOT in agricultural in modern agriculture was put forward.