In order to achieve the accurate variable fertilization during the critical growth period of wheat, the active remote sensing spectrometer named GreenSeeker was used based on nitrogen nutrition diagnosis for wheat, then the fertilization expert decision system and precision fertilization control system of wheat was explored by established the quantitative recommend fertilization model. The results indicated that the established fertilization recommendation model provided the theoretical evidences for variable fertilizer. The design for fertilizer recommendation system and variable control system could integrate the wheat nitrogen nutrition diagnosis, fertilization recommendation as well as the fertilization control with automatic functions effectively. On the basis of the design, running, and test of the GSM network wireless transmission and the electromagnetic valve remote control as well as the automatic batching and fertilization device, which made the response time of fertilization decision-making system and the fertilizer control accuracy reached to average 3.6 s（≤5 s） and 3.62%（＜5.0%）separately, therefore, the accuracy requirement for the remote variable controlled fertilization was achieved. Through the design of wheat fertilization decision-making and control system based on quick diagnosis, the real-time diagnosis and the intelligent recommendation as well as the remote variable fertilization of wheat was achieved.