We compared photosynthetic characteristics, pigment contents, chlorophyll fluorescences and anatomical traits in leaves of seedlings between 7 liana and 5 tree species under two light irridiances (4 and 35% of full sunlight) in a shadehouse in Xishuangbanna, SW China. The results showed that: (1) In the low light, lianas had lower photosynthetic capacity, whilst they had the greater increasement (lianas, 86.4%; trees, 61.5%) in photosynthetic rates responded to the high light level. Moreover, lianas had higher light compensation point (LCP) and light saturated point (LSP) than trees. (2) Maximum efficiency of PSⅡphotochemistry (Fv/Fm) was declined and non-photochemical quenching (NPQ) was increased in the mid-day for both lianas and trees. Compared to trees under the same light level, lianas had higher Fv/Fm values and were less photo-inhibited by the midday strong light. (3) Pigment contents per unit area decreased under the high light level. Lianas had higher pigment contents (eg. chlorophyll a, chlorophyll b, total chlorophyll, carotenoid content) per unit area and ratio of chlorophyll a and b than trees. (4) Lianas had higher specific leaf area (SLA) than trees although they had thicker leaves, which indicating thatthe density of leaves of lianas is lower.