Abstract: From June to September 2011, we had chosen 3 group pure plantations of Cunninghamia lanceolata in different ages and 3 group mixed plantations of C. lanceolata and Pinus massoniana in varied ages as samples, investigated the plant communities, and used the method of fence with pitfall trapto investigate amphibian communities. The results showed that: 1) the effects of forest age on amphibian niche were higher than those of species composition of plantations, and the biodiversity rule of shrub and herbaceous layer was same with the rule of amphibian niche width. 2) Amphibians in the same family had a high degree of niche overlapping and the competition was fierce. 3) The adaptability of amphibians to forest age change of plantations was different with plants, and in mature and over-mature stands, the niche width of amphibians became narrow and the number declined.