In order to investigate the live food value of microalgae for efficacious rearing of larvae and spats of bivalve, we studied growth rates of four microalgal species (Isochrysis galbana, Pavlova lutheri, Chaetoceros simplex, Tetraselmis tetrathele) cultured in different environmental conditions. These include changes in temperatures (20, 25, 30 and 35℃), salinities (20, 25, 30 and 33 psu) and light intensities (60, 100 and 140 μmol m-2 s-1). The growth rate of I. galbana was faster at 25℃ than that of 20℃. At 25℃ the highest growth rate of I. galbana was observed at 33 psu (0.413) and the lowest at 20 psu (0.368) in 10 days of culture (P < 0.05). The growth rate of I. galbana was lower at 25 psu (0.383) than that of 30 psu and higher than that of 20 psu (P < 0.05). Similar temperature and salinity-dependent changes were also found in P. lutheri and T. tetrathele. C. simplex showed faster growth rate at 30℃ than that of 25℃. The highest growth rate of C. simplex was observed at 33 psu (0.428) and the lowest at 20 psu (0.389) in 10 days of culture (P < 0.05). Upon exposure to the light with different intensities, all four microalgal species showed a significantly faster growth rate at 140 μmol m-2 s-1 than at 100 μmol m-2 s-1 (P < 0.05).