Objective To develop an automated greenhouse environmental monitoring and control system based on an NB-IoT low-rate narrow bandwidth networking and 5G low-power massive connection technology.Method Ultra-low power chip MSP430F149 was applied to collect environmental information. Using the NB-IoT's cellular networking platform and the cloud intelligent control system and combining multi-sensor fusion with fuzzy PID-grading control technology, greenhouse environment was controlled according to user needs.Result Using the automated system in greenhouse, the relative error of greenhouse environmental information collection was below 1%, the average control accuracy was 3.57% (±1.0 ℃), the transmission distance was not limited and the automatic regulation of crop growth temperature was realized.Conclusion The system is stable and reliable, and provides a favorable environment for plant growth as well as a strong technical support for crop research.