Abstract:The main objective of the study was to determine the effects of nutritional media and initial cell density on the growth and development of Spirulina platensis. This study was carried out at the Center for Incubation and Technology Transfer, Hue University from May 2015 to August 2016. In the first experiment, S. platensis was cultured in four different nutritional media, including Zarrouk, Spi-RIA3, Nisole and Thuoc medium (Vietnamese). Resulted showed that S. platensis grew significantly in the Zarrouk medium rather than in other nutritional medium at the same time, and gained the maximum density of 2,736.5 mg/L after 13 d inoculums, with specific growth rate of 4.987% per day and the time to doubling population of 0.139 d. In the second experiment, S. platensis was cultured in six different initial cell densities: 100, 400, 700, 1,000, 1,300 and 1,600 mg/L, and the optimum nutritional medium was Zarrouk medium selected from experiment one. Results showed at the initial culture density of 400 mg/L, the highest biomass was gained with the maximum density of 3,071.2 mg/L after 21 d inoculums, with specific growth rate of 9.15% per day and time to double population of 0.076 d. S. platensis biomass from culture in Zarrouk medium at initial cell density 400 mg/L obtained total protein of 51.98%, total lipid of 1.75%, total carbohydrate of 0.75%, carotene of 0.36% and total minerals of 5.2%, on a basis of dry matter.