To investigate the effects of different densities and sizes of spotted scat (Scatophagus argus) on production and nutrient recovery in integrated culture（IMTA） system of white shrimp, spotted scat and water spinach, an experiment was conducted using a 3×2 factorial design in 21 outdoor cement tanks (5 m×3 m×1.2 m). Combinations of two kinds of sizes (10.0, 30.0 g/ind) and three kinds of densities (1, 2 and 3 ind/m²) of spotted scat were set, while three additional tanks with shrimp monoculture were used as a control. There was no water exchange and feed input to all treatments was limited to the same amount. In comparison with monoculture, IMTA model increased the shrimp survival rate, total biomass and combined overall FCR remarkably. The combined nutrient recovery in IMTA tanks was significantly higher than in single shrimp tanks (P<0.05), ranging from 44.4% to 62.5% for total nitrogen and from 19.4% to 29.1% for total phosphorous. The optimal stocking density and size of spotted scat were 2 or 3 ind/m² and 30.0 g/ind.