With the development of technology of internet of things (IOT), video data plays more and more important roles in monitoring of facility agriculture. Aiming at the video data requirement of identification for greenhouse vegetable diseases, this paper presents a monitoring video capture system orienting the identification of greenhouse vegetable diseases according to the characteristics of diseases of greenhouse leafy vegetables. The monitoring video capture system utilized the technology of IOT and the information acquired by sensors and monitoring cameras in greenhouse. The monitoring video capture system achieved the goal of intelligent greenhouse monitoring video acquisition by using a designed greenhouse video acquiring method. The greenhouse video acquiring method fused the case based reasoning and fuzzy reasoning, more specially, monitoring videos can be acquired through the greenhouse video acquiring method by matching the data collected by sensors in real time with the combination of environmental conditions in knowledge base. The fusion of case based reasoning and fuzzy reasoning can make up the incompleteness of the use with single method of case retrieval and ensure the accuracy of the data. The system also consisted of the functions of real time monitoring data and real time monitoring video. The results showed that the recall of the monitoring video capture system was 95.4%, which indicated that the monitoring video capture system can meet the video data requirement of identification for greenhouse vegetable diseases.