This study was conducted to assess whether edible seaweeds, Turbinaria ornata and Gracilaria corticata can be partially replaced the fishmeal to promote the growth of the freshwater prawn, Macrobrachium rosenbergii post larvae (PL).Control was prepared with fishmeal, groundnut oilcake and soy bean meal as rotein sources, wheat bran as carbohydrate source, sun flavor oil as lipid source, and topica flour and egg albumin as binding agents. Isonitric experimental diets were prepared by 25% and 50% replacements of the fish meal with T. ornata and G. corticata separately. These feeds were fed to M. rosenbergii PL for 90 days. Among these 25% fishmeal replaced diets with T. ornata and G. corticata produced significantly better survival and growth when compared with control. Among the fishmeal replacement seaweeds, G. carticata was performed better than that of T. ornata. The 50% replacements of the fishmeal showed poor performance when compared with control. In the 25% fishmeal replaced categories, the muscle total protein, amino acid, carbohydrate, lipid and ash, profiles of proteins, amino acids and fatty acids, and activities of digestive enzymes, such as protease, amylase and lipase were elevated due to the influence of T. ornata and G. corticata. Thus, 25% replacement of the fishmeal with these algae is recommended for sustainable production of M. rosenbergii.