Abstract: Anuran tadpoles develop in water and depend on the food available in the system for nourishment and energy necessary for completion of their life cycle. Tadpoles of Leptobrachium smithi were collected from permanent running water systems from Rosekandy Tea estate in Cachar district, Assam. Taxonomic identification of the tadpoles was done by rearing them to adult stage under laboratory condition. Physico-chemical variables of water from where the tadpoles are collected were also analyzed. Tadpoles of different developmental stages 25-27, 28-30 and 31-40 (Gosner,1960) were selected for study. A qualitative analysis of food consumed showed that diet is basically composed of algae and detritus. A total of 30 genera belonging to five classes i.e. Bacillariophyceae, Chlorophyceae, Cyanophyceae, Euglenophyceae and Desmideaceae were recorded. The percent abundance and percent frequency of occurrences of different food items show that significant difference exists between the three different developmental stages but food items were almost similar in the different stages. Bacillariophyceae, Chlorophyceae and Euglenophyceae were important food in all the stages. The diet preference and choice of algae as food indicates that the conservation of habitat in terms of algal diversity is essential for the survival and completion of life cycle of the tadpoles and for successful survival of the anurans.