the great flood in Thailand B.E. 2554. damage to, Phra Nakhon Si Ayutthaya province, more than 99% of the area of all the Industrial Estate is located in the area of damage is a province, has been very much from last year.2555 Industrial Estate, all of the wall construction to protect against flood damage which may be caused to the Rojana Industrial Park Industrial Estate in the futureindustrial area surrounded by gardens of both 3-phase community is inserted in between the walls of each phase space these communities may become a water area or the area flood in the future.HEC - RAS to evaluate the impact of the flood defense wall of Rojana Industrial Park to the community by the neighboring flood scenarios before and after the flood protection wall model with HEC - RASDisplay a map information on the study can be used to evaluate the impact on the community will be made nearby and propose guidelines for the prevention and reduction of damage from floods in the future