A temporal XML indexing structure based on temporal encoding and linear order partition was studied. First, a temporal encoding method based on extended preorder encoding was proposed, by which the structural relationship between nodes can be determined. Second, based on detail analysis of relationship between time intervals, the concept of linear order partition was proposed, and algorithm to attain a linear order partition was also discussed. Then, a temporal structural summary was introduced which includes both structural and temporal information, and a temporal XML indexing mechanism—TempSumIndex was built based on temporal structural summary, then, both temporal querying and incremental updating algorithms of TempSumIndex were discussed. Finally, experiments were designed to compare the basic performance of TempSumIndex with existing temporal XML indexing methods, and the experimental results show that TempSumIndex has better performance.