Because the growth of crops in greenhouses relied on temperature and humidity, a temperature and humidity intelligent monitoring system for intelligent agriculture was established based on PLC and MCGS configuration technology. The overall design was illustrated, and the hardware system design, software system design and the operation and debugging of the physical system were elaborated. Experimental results demonstrate that the system can be used to effectively control the temperature and humidity inside the greenhouse. Additionally, it is easy to operate and has a high degree of visualization. It will provide a solution to traditional agriculture visualization and benefit the farmers significantly.