Nowadays, herbal extracts of the medicinal plants are important in the aquaculture sector for the enhancement of growth and reproductive factors of freshwater fishes. In India, Labeo rohita is one of the most commonly cultured freshwater fish for human consumption. Phyllanthus niruri (Family: Euphorbiaceae) has various pharmacological properties due to their phytocompounds which are used to treat various ailments. After acclimatization, the L. rohita adult fishes (n=10) were treated with leaf extracts of P. niruri (5, 10, 20, 40 and 80mg/gm) based diet for 14 days. Fish gill, muscle and liver tissues - total glucose, total protein, total cholesterol, transaminases (AST, ALT) and glutamate dehydrogenase enzymes were statistically analysed. Our study concluded that P. niruri leaf extract based diet to the freshwater fish L. rohita showed an improved biochemical parameter than control fishes.