Abstract: With batch culture, the effect of temperature, light intensity and pH offer on the growth rate and maximual cell density of Isochrysis galbana Parks were studied in the work by gradient experiments. Nutrients including N3+, P5+, Fe3+, NaCl and the manner of CO2 were also studied by orthogonal or contrastive test. The results showed that light intensity 3220lux, temperature 24℃ are the optimum culture condition for Isochrysis galbana Parks. It liked growing in the alkaline environment, pH8.0. Concentrations of other nutrient factors were optimized by orthogonal test: N3+ 0.04039g/L, P5+ 0.0044g/L, Fe3+ 3.90mg/L and NaCl 20.476 g/L. Cultured with this optimal medium, the cell growth speed, TTC and biomass productivity increased significantly. The biomass was 1.432 times as much as before. The harvest yield (dry weight) was 0.6613g/L with the aeration rate 10min/ 3 time /day under the best cultural condition. The ultimate biomass reached the most, was 1.815 times as before especially.

Key words: Isochrysis galbana Parks 3011, growth rate, nutrients, cultural condition, optimization