Abstract: 23-year Machilus versicolora was felled for wood specimen from secondary forest in Nanjing, Fujian province. They were treated by Gloeophyllum trabeum and Coriolus versicolor for testing the natural durability method of wood natural decay resistance in this paper. Microstructure and chemical compositions of specimen before and after degraded were characterized by SEM, FTIR, XRD and TG-DSC. The result showed that the natural durability M. versicolora specimen to C. versicolor reached grade I (strong resistance) while only grade Ⅲ (slight resistance) to G. trabeum. The relative crystallinity of M. versicolora specimen increased after treatment of C. versicolor, but it decreased after treatment of G. trabeum. During the third stage of pyrolysis, mass loss rate of specimen treated by G. trabeum was larger than that before test and treated by C. versicolor. Compared with before test, the maximum exothermic and endothermic reaction temperature for specimen shifted to higher temperature.