Abstract: For the purpose of application of wireless sensor networks in vegetable greenhouses’ environmental monitoring, the author studied several ad hoc routing algorithms. Through the classification and comparison the advantages and disadvantages of different routing algorithms such as ABR, TORA, DSR, DSDV, AODV and so on, the author came to a conclusion that the AODV routing algorithm was suitable for application in vegetable greenhouse because it could reduce the overhead and communication delay at the same time, and therefore, selected the working principle of AODV algorithm for deep research. By simulating the wireless sensor network which using the AODV algorithm by NS2 and NAM network simulation tools, the author analyzed the simulation data by gwark and gnuplot tools, researched the changes of network transmission delay and packet loss rate when the number of nodes were increasing in a certain area, and found the relationship between the number of nodes and the quality of communication, thus to provide a theoretical evidence for the practical application of this wireless sensor network algorithm in vegetable greenhouses.