Abstract: Studying the water conservation function of artificial forests in the basin plain lake area of Yangtze river is great significance to guide the afforestation and ecological restoration along the Yangtze riverbank. In this paper, the water conservation capacity of litter layer and topsoil of 7 different forest types were analyzed and compared by the soaking method based on field investigation. The results showed that, （1) The litter accumulation of semi-decomposed layer was larger than that of undecomposed layer, and the -Taxodium ascendens forest had the largest litter accumulation among the undecomposed layers, while the Salix jiangsuensis forest had the largest litter accumulation among the semi-decomposed layer. The total litter accumulation of Taxodium ascendens forest was largest, which was 3.90 t/hm². （2) The maximum water holding rate of the undecomposed layer (263.63%-530.86%) was greater than that of semi-decomposed layer(209.17%-277.91%). The maximum water capacity of the undecomposed layer and the semi-decomposed layer were 0.95-4.48 t/hm² and 4.15-6.02 t/hm²， respectively, and the Taxodium ascendens forest and Salix jiangsuensis forest exbihited highest maximum water capacity-correspondingly. (3) The effective storage capacity of undecomposed layer was 0.44-3.11 t/hm², of which the Taxodium ascendens forest was highest. And the effective storage capacity of semi-decomposed layer was 0.75-3.82 t/hm²， of which the Platanus acerifolia forest was highest. Among all the forest types, the total maximum water holding capacity and the total effective storage capacity of Taxodium ascendens forest were both largest and its values were 9.61 and 5.64 t/hm²， respectively. (4) With the-immersion time prolonged, the litter water holding capacity increased significantly at the beginning, and then slowed down, and finally reached saturation, the relationship between them  showed as logarithmic function. Otherwise, With the immersion time prolonged, the litter water absorption rate was higher in the early stage, then decreased sharply, and finally approached 0, the relationship between them was power function. （5) The maximum and effective water holding capacity of Salix jiangsuensis forest were largest in topsoil layer among all the forest types, which was 1 116.27 and 213.27 t/hm²， respectively. For the litter layer, the water conservation ability of Taxodium ascendens forest was better than others, while, the water conservation ability of Salix jiangsuensis forest was better than others in the topsoil. In general, Salix jiangsuensis forest is superior on water conservation comprehensively.