A feeding experiment was conducted to develop non-fish meal and non-fish oil diet for red seabream by using plant protein source and Schizochytrium meal which is rich in 22:6n-3 (DHA). Three iso-nitrogenous and iso-lipidic experimental diets were prepared (CP 41.2% ± 0.4%, CL 16.4% ± 1%). Control diet contained both fish meal (40%) and fish oil (6%). In the second diet, fish meal was replaced by plant meals (soy protein concentrate, soybean meal, corn gluten meal) [FO]. In the third diet, fish meal and fish oil were replaced by algae meal (Schizochytrium sp. powder) and plant proteins [AO]. Duplicated groups of juvenile red seabream (8.8 g ± 1.5) were fed the experimental diets for 12 weeks to near satiation. There was no statistical difference among treatment in specific growth rate. Feed conversion ratio of AO diet group was higher than that of control. In wet basis, whole body protein level was significantly higher in AO diet than FO group while lipid content was lower than control group. In fatty acid profile, AO group had significantly lower 18:4n-3, 20:4n-3, 22:5n-3 and 20:5n-3 (EPA) level, but significantly higher 18:3n-3 and DHA level than the other two diet fed fish. The results might suggest that further developments in microalgae diet offer a promising lipid source of n-3 PUFA as essential fatty acid on marine fish. And it showed possibility to develop non-fish meal and non-fish oil feed for marine aquaculture fish by using microalgae.