This paper clarified the basic idea of structure 19 orders Steiner triple systems. The definition of edge matrix was given,which can be decomposed into complete graph and complete triple graph.Then the complete graph and complete triple graph can be decomposed respectively to obtain Steiner triple systems. Based on the Kv sub graph decomposition,the enumeration method and construction method of Steiner triple systems were given.And two methods were used to give the specific construction processes and count of 19 orders Steiner triple systems. It can be concluded that the construction method and enumeration method of Steiner triple systems are effective.