Abstract: China has a large number of historic wood structure buildings. To test and evaluate the condition of historic wood structures reasonably and effectively is demanded by condition assessment of the wood structures for protection and restoration of the buildings. Nondestructive testing of historic wood structures is a test and evaluation technique to wood properties, oriented by inspecting and evaluation of wood structure safety, and in situ application and actual inspection demands. The testing content mainly includes two aspects: non-destructive testing of defects and non-destructive testing of physical and mechanical properties. Assessing concealed defects of wood structures and wood members is the main task and difficult work of the nondestructive testing of historic wood structures. Firstly, this paper introduces the composition of wood structures of ancient buildings, and summarizes the nondestructive testing content and current common nondestructive testing methods. Then, the application and research progress of the inspection of concealed defects, the classification of wood members and the influence of decay on mechanical properties of historic wood are summarized. Finally, the research status of nondestructive testing of historic wood mechanical properties and effect of natural aging on wood properties of historic buildings is summed up. The paper should be able to inspire and help relevant people who engaged in the inspection application and scientific research of protection technology of historic building wood structures.