Thailland is an agriculture based county which many inhabitants are farmers. knowledge on soil is scattered in many place, this is difficult to search for soil topics. this paper present steps to creare soil ontology to aid in the soil knowledge search. this soil ontology is also compatible to be used by other information systems.it further helps in searching of knowledge from multiple sources on the internet and supports knowledge sharing and knowledge reuse which is the important process in knowledge management. as a result, the seed soil ontology contains 84 nodes and 83 relationships. establishing soil ontology has been revieweb by a soil specialist, it is accurate and can be impelemented effectively.