Abstract:This paper researches the effects of acid rain stress on photosynthetic and physiological characters of typical seedlings（Pinus massoniana Lamb.,Cunninghamia lanceolata (Lamb.) Hook., Castanopsis eyrei (Champ.) Tutch., Castanopsis sclerophylla (Lindl.) Schott.）in subtropical regions of China. Judging increasingly serious acid rain would affect forest in subtropical regions of China, in order to restoring degenerate forest better. The results show that under acid rain stress, the height growth of C.eyrei,P. Massoniana is influenced slightly, while it will promote the height growth of P. Massoniana. In the treatments with pH4.0, the diameter growth of C.eyrei,P. Massoniana,C.lanceolata have been increased. With increased of acid rain concentration, the photosynthetic rate (Amax) of C.sclerophylla,C.eyrei,P. Massoniana is decreased under different acid rain treatments, it shows that photosynthetic capacity of this three seedlings have been affected already, especially the broad-leaved species, the highest maximum photosynthetic rate (Amax) of C.sclerophylla, C.eyrei reduced by 30% and 25% under acid rain stress respectively.