Seedlings of Vallisneria asiatica (SVA) were planted in the waters with turbidity of 30NTU, 60NTU, 90NTU or 120NTU. The turbidity of the water was controlled by sand particles smaller than 100μm in diameter, and the effect of water turbidity on the growth of SVA was examined. The photosynthetic fluorescence characteristics of the leaves attached on silts was determined in situ by a developed, submersible, pulse-amplitude modulated (PAM) fluorometer, diving-PAM in actinic irradiance. The activities of superoxide and peroxide of the leaves were also determined. The experimental results indicated that the stains number and leaf numbers, and leaf width of SVA decreased significantly as the turbidity of water increased after exposing the seedlings in turbid water for 60 days. However, the leafs grew faster in the water with turbidity of 30NTU than that in the control water. With the extension of experimental time, the plants gradually died in turbid water with high silts content (turbidity ≥ 60 NTU). In contrast, seedlings can grow and develop normally in the turbid water with a turbidity of 30 NTU. The silts amount attached on leaves increased gradually with bloom of the plants in autumn. The effective quantum yield of photosystem II, photochemical quenching and electron transport rate of leaves attached on silts determined in the turbid water of 30NTU were higher than those measured in the control water. However, the activities of superoxide and peroxide of the leafs did not show a significant difference by comparison with the control syetem. It was shown that silt attachment could avoid damage from high irradiance in autumn to photosynthetic system II of the leaves at low turbidity of water, consequently maintain photosynthetic capacity of the leaves. Therefore, seedlings of V. asiatica might be adapted to low turbid shallow water of silts (turbidity ≤ 30 NTU)，and normally grow and develop, and breed. It is also suggested that the best seedlings were germinated from winter buds or rhizome of V. Asiatica..