The role and distribution of fresh water algae was surveyed at Wangdeungjae Wetland of Mt. Jiri, a
high mountain swampy land. Mean environmental factors were as follows; temperature was 17.6 ℃, pH was 6.3,
conductivity was 24.6 (S/㎝, TN was 0.6 ㎎/L, TP was 0.09 ㎎/L, and Chl-a was 11.9 ㎍/L, respectively. Algae
were appeared 159 species(Chlorophyta 87, Bacillariophyta 56, Euglenophyta 11, and Cyanophyta 5). Desmid of
Chlorophyta was 56 species, and dominant species was Aulacoseira distans of Bacillariophyta. To analyze food
chain of the water ecosystem, we performed analysis of tadpole\'s stomach captured in the wetland. Tadpoles
ingested mainly algae, and Aulacoseira distans was found in most quantity. Based on this study, algae take role of
the primary producer as well as the prey of higher level predators(e.g. tadpoles) in the water ecosystem of
Wangdeungjae Wetland.