I think, It should be very difficult to develop enterprise architecture plan in hospitals systems because of Different departments have different systems development. Thailand is in a developing country.The development of the EA health system is not clear.The obvious is the 43 file system But has not used to occur as a system and many problem such as completely ,correct and on time .Application development into many Causing the work load of the staff ,People cannot access information and has not yet integrated the information with other agencies. System Development EA Health System is absolutely necessary to develop the whole system. Like US that mobilize various experts and resource to develop, there are organizations that look after the system Whole health systems and information safety. Thailand should begin to develop the basic EA system of In various departments first in order to be an important foundation for future development Should start with a small organization Expanding to a larger image to create an integrated database with the same format and application development that can reduce unnecessary workloads And able to use the information most efficiently.